First it was Corey Kluber. And now, Jameson Taillon.

If you were told two years ago that heading into the 2021 season these two would be a part of the Yankees’ rotation, it would be a stunning development. After all, the first is a two-time Cy Young Award winner who was coming off a 2.89 ERA in 215 innings, and the other was a 27-year-old former second overall pick who had just posted a 3.20 ERA in 191 innings.

But that was two years ago. Today, both are coming off Tommy John surgeries that caused them to miss the 2020 season -- with Taillon’s being the second Tommy John procedure of his career -- and both come with question marks as to whether they can reclaim their prior form. If they can't, New York's rotation could become its most glaring weakness after the departures of Masahiro Tanaka, J.A. Happ and James Paxton.

The Yankees are betting on big upside winning out over big risk on Kluber and Taillon. So let’s break down how Taillon, their latest acquisition who is headed to the Yanks in a deal that sends four prospects to Pittsburgh, might help New York if he stays healthy and returns to form.

He gets ground balls

Fly balls at Yankee Stadium? Not advisable, especially if they’re to right field. So a ground ball pitcher is a good thing, and during Taillon’s four seasons from 2016-19, his 50 percent ground ball rate ranked 25th out of 107 starters who had at least 1,250 batted balls in play against them. And when hitters do put the ball in the air against Taillon, those balls seldom find their way over the wall -- he ranked 16th of 122 starters (minimum 250 fly balls from 2016-19) with just 13.5 percent of fly balls against him resulting in home runs.

How important is getting opponents to hit the ball on the ground in the Bronx? Since Statcast began tracking in 2015, only two MLB ballparks rank higher than Yankee Stadium in percentage of fly balls that resulted in homers -- Coors Field and Miller Park. Yankee Stadium also ranks sixth among current ballparks in expected batting average on fly balls -- .262. Expected slugging percentage? Seventh (.829).

He induces weak contact

Ground balls? Check. What about quality of contact, another important piece to the puzzle, but especially so at a hitter’s park like Yankee Stadium?

From 2016-19, Taillon’s 87.6 mph average exit velocity on balls in play ranked in the top third of starters with a minimum of 1,250 batted balls against them. He was even better in terms of the percentage of batted balls that were barreled, finishing tied for second out of 107 starters over that span -- Taillon’s 4.4 percent figure was tied with Carlos Martinez and behind only Noah Syndergaard’s 3.6 percent.

That would help a Yankees rotation that ranked 21st in the Majors in barrel percentage last year.

He’s got a good curveball

In his only full season in the Majors to this point, which was in 2018, Taillon ranked 19th of 112 starters who had at least 50 curveballs swung on with a 37.8 percent whiff rate. He ranked 17th of 92 starters (min. 30 at-bats that ended on a curveball) with a .179 expected batting average against.

He doesn't walk many guys

Taillon has shown excellent control of his arsenal when healthy. From 2016-19, his 5.5 percent walk rate placed him 19th of 139 pitchers who faced a minimum of 1,500 batters over that span. His career strikeout-to-walk ratio is 3.6.

If he's healthy, look out

Rejoining former Pirates teammate Gerrit Cole, and likely to slot in behind Cole and Kluber in the Yankees' rotation, Taillon could be a tremendous pick-up for New York if he stays healthy. That's a big "if," but at a salary of $2.25 million for 2021, which also keeps the Yanks under the payroll tax threshold for the year, the high upside might be really high.

If it doesn't work out, however, it could leave a gaping hole in the rotation of a club that has its sights set on following the Dodgers in snapping a long World Series title drought.