The trade deadline has passed -- there was more activity than I expected, I am pleasantly surprised -- and we are now in the stretch run of the 2020 MLB season. The next two-and-a-half weeks will decide postseason races as well as the awards races in this unusual season. It's been a weird one. A fun one, but definitely a weird one.

Last week we examined Jesse Winker's breakout season, among other things. Now here are three other MLB trends to keep an eye on.

Diaz's really good, really weird season

Edwin Diaz
NYM • RP • #39
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Without question, Edwin Diaz's first season with the New York Mets was a disaster. He went 26 for 33 in save opportunities last year, allowed 15 home runs in only 58 innings, and finished with a 5.59 ERA. Opponents hit .258/.332/.502 against him, which is about what Matt Chapman hit last season (.249/.342/.506). It hard to fathom Diaz being that bad, but he was.

This season Diaz has been dominant, but also sort of bad? Maybe a little of both? He's having a weird season. First and foremost, yes, Diaz has been dominant. I don't know what you call 38 strikeouts in 18 innings otherwise. His 48.7 percent strikeout rate is the highest in baseball among pitchers with at least 18 innings. There's also this:

Average exit velocityExpected batting averageExpected slugging percentage


87.3 mph




87.8 mph




90.1 mph




84.2 mph



When he's not striking everyone out, Diaz is generating a ton of weak contact. His average exit velocity allowed and expected batting average and slugging percentage (based on exit velocity and launch angle) all rank in the top four percent in the game. Those numbers are all in line with (or better than) his 2017-18 seasons with the Mariners, when he was arguably the best reliever in the sport.

Why then are opponents hitting .423 -- .423! -- when they put the ball in play against Diaz? His overall batting average allowed is .197, which is obviously excellent, but all that weak contact has resulted in more than two out of every five balls in play falling in for a hit. Diaz's BABIP was an insanely high .381 last year and a much more normal .258 from 2017-18. This year though, it's .423.

The terms "luck" is overused in baseball analysis (industry secret: "luck" is often used to describe something we can't explain), but in Diaz's case, yeah, he does seem to be getting a little unlucky. Consider these three hits -- nearly 40 percent of his season total hits allowed (three of 13) -- that didn't leave the infield:

Based on the quality of the contact, those three batted balls had expected batting averages of .050, .260, and .070, respectively. All three went for hits. On one hand, when you give up such weak contact, you're going to be susceptible to infield singles. On the other hand, come on man! Poor Edwin. He had a rough season last year and deserves to have some bounces go his way.

That isn't to say it's all bad luck for Diaz. He's walked 11 batters in those 18 innings, which is far too many, and the two home runs he's allowed were both backbreaking game-tying shots with one out remaining. Diaz has been very Dr. Jekyll and Mr. Hyde. He can be utterly untouchable at times -- at most times, I'd argue -- yet every once in a while the monster shows up to blow the game.

Diaz, who is still only 26, spent part of his offseason working with Hall of Famer Pedro Martinez, specifically on his slider, a pitch that deserted him at times last season. Last season opponents hit .297 and missed with 43.2 percent of their swings against his slider. This year it's .129 and 61.1 percent, numbers that are in line with his Mariners years.

"It wasn't anything that I changed significantly. It was mostly the minor adjustments that I felt I needed to make and I actually put those to work this offseason," Diaz told SNY in February. "... I feel good. I feel happy about it, with all the work that we've done this offseason with the slider. I feel really good."

In terms of raw stuff and pure bat-missing ability, few pitchers in the game can match Diaz. It's top one percent stuff. It really is. He is still prone to the occasional meltdown, which makes him like most relievers, but the ability to pile up strikeouts and limit hard contact is what made him so great earlier in his career. That was absent last year. It has returned this year, even if more batted balls are going for hits than you'd expect.

Run Blue Jays run

With wins in 17 of their last 21 games, the Toronto Blue Jays have moved into second place in the AL East, and they have a firm grasp on a postseason spot. They're 3 1/2 games up on the No. 9 team and Sportsline puts their postseason chances at 94.7 percent. If you want a second opinion, FanGraphs has them at 92.7 percent. The Blue Jays are close to a lock to play in October.

The Blue Jays are where they are thanks to a great offense (5.00 runs scored per game, 8th best in MLB) and really good run prevention (4.40 runs allowed per game, 11th best in MLB). The one negative is baserunning. The Blue Jays are a very aggressive and occasionally careless team on the bases. Some baserunning ranks:

  • Outs on the bases: 21 (most in MLB)
  • Extra-base taken rate: 36 percent (third worst in MLB)
  • Baserunning runs (per FanGraphs): minus-0.8 (17th in MLB)

Run until they tag you, as they say. The Blue Jays are taking that to heart this season. They run themselves into a lot of outs. Those 21 outs on the bases are nearly double the league average (12.7) and Toronto ranks top four in outs made at second base (seven), third base (four), and home plate (seven). They're sixth with three outs at first base.

"It's player development in the big leagues," Blue Jays manager Charlie Montoyo told reporters, including Keegan Matheson of, following a game particularly heavy on baserunning mistakes earlier this season. "We're still young, but we cannot make those mistakes."

In the grand scheme of things, baserunning is not the most valuable skill in the world. The difference between the best and worst baserunning teams each year is typically around 40 runs -- the difference between the best and worst hitting teams is about 400 runs, for comparison -- and that's not much when spread across 162 games. If you're going to be bad at something, baserunning is a good thing to be bad at.

That said, the difference between good and bad baserunning can be enormous in a single game. Across the full season it tends to even out, but, in an individual game, that extra 90 feet can change everything. There's a reason speedsters like Billy Hamilton keep getting work. In the moment, baserunning can be incredibly valuable. Or detrimental if you're bad at it.

It would be unfair to call the Blue Jays a team of bad baserunners, but they are careless at times, and it hurts them more than it helps. With an average age of 25.9 years, the Blue Jays have the youngest collection of position players in the game, and the hope is their baserunning will improve with experience. Right now though, they push the envelope a little too much, and it could cost them in a big spot down the stretch.

"We're still developing," Montoyo told reporters earlier this month, including Gregor Chisholm of the Toronto Star. "Even though we're in the big leagues, we have a lot of young kids ... You have to keep developing and you have to keep teaching. That's my conversation to the coaches, just keep talking to them. That's part of development. They're going to get better and they're going to make mistakes. And when they make mistakes, you have to tell them why they did it and how they can get better."

Could the MLB strikeout rate decline?

It is no secret baseball is a strikeout-heavy game these days. MLB has set a new single-season strikeout rate record in each of the last 12 seasons, starting at 17.5 percent of plate appearances in 2008 and gradually climbing to 23.0 percent of plate appearances in 2019. There have already been more strikeouts in 2020 (10,778) than there were in the entire 1954 season (10,218).

Hitters have struck out in 23.1 percent of their plate appearances this year, up ever so slightly from last year and on pace for a new single-season record. The average strikeout rate increase from 2008-19 was 0.5 percentage points per year. This year it's only 0.1 percentage point. Could the league strikeout rate actually go down this year? Consider:

1. MLB is using the universal DH. Pitchers are really bad at hitting. Not just hitting, they're bad at simply getting the bat on the ball. From 2017-19, pitchers struck out in 41.3 percent of their plate appearances. All other players struck out 21.9 percent of the time. Without question, the universal DH has slowed the increase in the league-wide strikeout rate this year. 

2. No Sept. call-ups. Under the old roster expansion rules teams would load up their rosters with extra relievers and extra bench players in the season's final month. That equaled more strikeouts because a) managers could more easily match up their bullpen, and b) more at-bats went to overmatched youngsters. From 2017-19, the strikeout rate was higher in September (23.0 percent) than all other months (22.2 percent). There is no Sept. roster expansion this year, though teams did play the first two weeks with a 30-man roster and every week since (and every week going forward) with a 28-man roster.

3. Fewer extra innings. MLB implemented the extra innings tiebreaker rule this season to prevent marathon games and extra innings tend to be filled with strikeouts. Over the last three seasons the strikeout rate was higher in extra innings (23.1 percent) than the first nine innings (22.3 percent). I reckon that's because more than a few hitters try to hit that game-winning home run and be a hero, among other things. Extra innings have a much different look and feel this year though.

Strikeouts have been trending down this year. The league strikeout rate was 23.6 percent in July, after hitters came out of the short summer camp. It dropped to 23.2 percent in August and again to 22.2 percent so far in September. With 19 days remaining in the regular season, is there enough time to drop the league average under 23.0 percent and not set a new strikeout rate record for the first time since 2007? I think it's possible, yeah, but it'll be close.

As much as I love this sport, I loathe the lack of action.'s Sean Forman recently noted MLB is averaging three minutes and 44 seconds between balls in play this year. It was under three minutes as recently as 2007. Look at this graph:

Yeesh. The lack of action (i.e. the continually increasing time between balls in play) is the worst part of experiencing this game as a spectator. There's so much time spent on nothing, really. Lowering the strikeout rate alone won't fix that, but it will help, and even if MLB sets another new strikeout rate record this year, I hope the rate of increase slows considerably.