Note: I wrote about Reynaldo Lopez to lead the waiver wire piece Tuesday morning, but I wanted to dive deeper into the changes he has made in the early going this season.

The Reynaldo Lopez we saw who pitched 47 2/3 innings in the majors last season wasn't the one we hoped to see. After striking out 24.4 percent of opposing batters in 154 innings in his Triple-A career, Lopez struck out just 14.5 percent in his eight starts with the White Sox.

Lopez threw hard, but was shockingly hittable, sporting a below-average swinging strike rate of 9.0 percent. The problem? His best swing-and-miss pitch was his changeup, and he had a below-average swinging strike rate with that pitch, 13.2 percent compared to 15 percent for changeups league-wide. His 5.7 percent swinging strike rate on his curveball was less than half of the league average for that pitch type.

Coming up through the minors, Lopez's curveball was considered his better secondary pitch, and it was effective in his cup of coffee in 2016. However, he clearly decided a change needed to be made, because Lopez has largely ditched the curveball in the early going this season. According to BrooksBaseball.com's PITCHf/x data, Lopez threw just seven curveballs on 106 pitches Monday against the A's, and has thrown just 10 through three starts.

That curveball this season has had an average velocity of 74.8 mph, compared to 79.5 last season, so it's a slower pitch with more break. He has replaced his old curveball for a pair of harder pitches: a slider that has averaged 83.9 mph, and a cutter that has averaged 86.2 mph, and it's pretty clear what he's trying to do with those two pitches: 

Reynaldo Lopez pitch usage

Fourseam Sinker Cutter Slider Curve Change
vs. LHB
All Counts 54% 0% 11% 4% 9% 22%
First Pitch 60% 0% 0% 0% 20% 20%
Batter Ahead 64% 0% 0% 3% 6% 28%
Even 50% 0% 13% 0% 13% 25%
Pitcher Ahead 48% 0% 24% 10% 7% 10%
Two Strikes 45% 0% 29% 10% 0% 16%
vs. RHB
All Counts 59% 1% 15% 17% 1% 8%
First Pitch 63% 0% 12% 16% 2% 6%
Batter Ahead 66% 0% 7% 14% 0% 14%
Even 61% 1% 16% 15% 1% 6%
Pitcher Ahead 51% 0% 20% 22% 0% 7%
Two Strikes 55% 2% 17% 18% 0% 8%


Lopez gave up an .808 OPS to left-handed batters last season with just a 10.8 percent strikeout rate. Lefties hit .295 with a .659 slugging percentage against his changeup and curveball, so he clearly needed a new look. In the offseason, he worked with pitching coach Don Cooper on the cutter as a weapon against lefties, and so far he has a 32.0 percent strikeout rate against lefties. It's working.

Whether it will keep working remains to be seen, but at the very least we can say with some certainty that we aren't dealing with the same Reynaldo Lopez who was so underwhelming in 2017. This version still has his flaws. He's giving up too many batted balls in the air and too many walks, two issues that can sink even the most talented pitchers.

However, Lopez was a pitcher who needed to adapt in order to secure a major-league job, and that's what he's done. It may not work, but it didn't look like what he was doing before was going to work either. This new version of Lopez at least has a chance, both against lefties and overall. Whereas before he looked like he might be fated for a bullpen role, he might just have the arsenal to last as a starter, with five distinct pitches. 

When you throw this hard (averaging 96 mph with his fastball this season), the margin for error is a lot wider, and the ceiling is a lot higher. With these changes, Lopez may be making the adjustments he needs to get there.