We can learn only so much from a pitcher's first couple appearances. New behaviors aren't necessary going to carry over from one start to the next, and even if they do, the results may not follow.

But when those behaviors seem calculated and there's a mountain of data backing up the results, that's when there's reason for optimism despite the absurdly small sample.

For these four, I wouldn't say I'm buying at all costs -- their owners may be looking to gouge you given the way they've started the season -- but I'm not looking to sell high. And I'm not putting limits on their ceilings either.

All were at one point thought to have big upside, and they may be taking the steps to capitalize on it now.

Patrick Corbin
WAS • SP • 46
Wednesday vs. Dodgers
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Patrick Corbin's first start didn't generate the headlines of this second, arguably career-best one, but he struck out eight over 5 2/3 innings, which should have been our first clue something was up.

His arsenal change is a fairly dramatic one that I could see becoming more common in an era when hitters are geared up for high-90s fastballs, making them more vulnerable to secondary stuff. He has essentially made his slider his primary pitch, throwing it 54.1 percent of the time against the Dodgers, accounting for 17 of his 20 swinging strikes in this one.

It reminds me a little of Brad Peacock last year, who went from barely throwing a slider to throwing it more than any other pitch, and we saw the breakout that resulted from that. The difference for Corbin is he began the transition last year, upping his slider usage from 25.7 percent in 2016 to 37.4 percent, according to BrooksBaseball, and having that head start allows him to manipulate the pitch a little better now. He varied the speed on it so much Wednesday that BrooksBaseball actually classified a third of his sliders as curveballs -- a pitch he has never thrown before.

If his command of it has also improved from a year ago, he could be in for more starts like this one.

Dylan Bundy
MIN • SP •
Wednesday at Astros
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We already knew what it'd take for Dylan Bundy to break out: He'd have to trust in the slider that once made him the game's top pitching prospect and that he reintroduced to his arsenal last season after years of arm troubles. The problem is he didn't go all the way with it, throwing the pitch only about 15 percent of the time during the middle months.

So for the stretches of the 2017 when he featured it 25 percent of the time, which include his first five starts and his final eight, he had a 2.82 ERA, 1.01 WHIP and 9.0 strikeouts per nine innings. For the other 15 starts, he had a 5.61 ERA, 1.37 WHIP and 7.2 strikeouts per nine innings.

Guess how much he's throwing it this year? In his first start March 29 against the Twins, when he struck out seven over seven shutout innings, BrooksBaseball had it at 27.6 percent. In this most recent start Wednesday against the defending World Series champions, it was 24.5 percent.

Now, since he didn't keep it up last year, there's always a chance he shies away from it again. But seeing as he went back to it -- a trend that has continued into this season -- I'm hopeful he has learned his lesson and knows what he needs to do to succeed now.

Mike Foltynewicz
TEX • SP • 20
Wednesday vs. Nationals
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The most available of these pitchers at 66 percent ownership in CBS Sports leagues, Mike Foltynewicz also has the lowest floor and the thinnest reason for optimism. But for at least one day Wednesday against the Nationals, he was the pitcher so many of us  have hoped he'd be.

Already blessed with a fastball that brushes triple digits and a good enough swing-and-miss slider, Foltynewicz has nonetheless suffered against lefties throughout his career, surrendering a .308 batting average and .879 OPS to them last year. He's the definition of a pitcher who's "just a changeup away."

And against a lineup with a couple big lefties Wednesday, he threw his changeup 20 percent of the time. Only six times last year did he throw it more than 10 percent.

It was up there with his fastball and slider in terms of whiffs, too, so it seems like a good enough offering to keep lefties honest and allow his big fastball to play up. We have no idea how intentional it was or if it'll continue, but again, he's the most available of these four.

Jameson Taillon
NYY • SP • 50
Monday vs. Twins
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Not as current as the other three but worth circling back to, Jameson Taillon made a more subtle change to his arsenal in his season debut against to his Twins, leaning more on his four-seam fastball (throwing it 46.2 percent of the time, according to BrooksBaseball) than his two-seamer (throwing it 22.0 percent of the time).

It was the reverse of most of his career, but for most of his career, he hasn't been the bat-misser he was Monday, his nine strikeouts equaling a career high. And the four-seamer was primarily responsible, accounting for half of his swinging strikes. It's the more difficult of the two pitches to square up, resulting in a .275 batting average last year vs. .333 for the two-seamer (.286 vs. .309 two years ago), and he seemed to realize it late in the year. His final two starts featured some of his highest four-seamer usage all season, and he allowed two runs on eight hits with 11 strikeouts in 12 innings between them.

If he has a plus fastball to pair with this changeup that seems to change direction mid-flight ...

... we're talking serious upside.