Oakland A's rotation roundup: Reinforcements have arrived

The Oakland A's rotation has gone through a bit of a shakeup as we approach the end of April. Eric Surkamp is back in the minors after filling in on emergency duty to begin the year, and Chris Bassitt is on the disabled list due to his elbow. In their places, lefty Sean Manaea and righty Jesse Hahn will pitch Friday and Saturday. After that we don't yet know what order the rest of the guys will go in, so here is the whole group in no particular order:

Sonny Gray
Rich Hill
Sean Manaea
Jesse Hahn
Kendall Graveman

Triple-A: Eric Surkamp
Rehabbing in minors: Henderson Alvarez

DL: Chris Bassitt, Felix Doubront

Let's take a quick look at one key number for each guy to see where the rotation stands.

Sean Manaea, LHP | 1

That's 1, as in No. 1 on our preseason Community Prospect List. If you have shortstop Franklin Barreto in the top spot, then Manaea is still the No. 1 pitcher in the system. Either way, this is it, folks. If you get at all pumped about an exciting new youngster coming up to the bigs, then this is the one to get up for. If this is your first day at Athletics Nation and you've never heard of Manaea, or you've been waiting until his promotion to learn about him, then click here to read all about the towering lefty. The 24-year-old throws hard, and he piles up the strikeouts -- in his first three starts for the Triple-A Nashville Sounds, he had 21 Ks in 18 innings. Welcome to the Throwin' Samoan!

Jesse Hahn, RHP | 49 + 72

Those are the number of pitches he threw in his last two outings for Triple-A Nashville. His start on April 19 was rained out, and the next morning the Sounds opted to pull him early so that he could stay on his normal rotation and go again four days later. They abbreviated that next start as well to ease him back up toward a normal workload, which means he hasn't made a full, normal start since April 13. Perhaps it would have been preferable to give him one more full outing in the minors just to be safe, especially after reports of a blister issue, but the injury to Chris Bassitt forced Oakland's hand. Besides, on the grander scale, it was time to quit messing around and get Hahn back in the bigs where he belongs.

Rich Hill, LHP | 33.6%

That's his strikeout rate, meaning he has fanned one-third of the batters he's faced. That mark is good for third among all MLB starters, behind Noah Syndergaard and David Price and just a hair ahead of Jose Fernandez. Hill has already registered two 10-strikeout performances in his first five starts. There's more to pitching than just Ks, and indeed a couple of his outings have been subpar overall, but his calling card is missing bats and he's done that so far. His last start was his most encouraging due to the fact that he didn't issue a single walk, which helped him last a season-high seven innings.

Sonny Gray, RHP | 2

That's the number of innings he went in his last outing, making it the shortest start of his career. In fact, it was only the fourth time that he's failed to make it through five innings in a start. Sonny hasn't been at his sharpest so far, and nowhere is that more evident than his walk totals -- 15 through his first five games. He's walking nearly twice as many batters as last year, which you can look at in terms of BB/9 (2.6 up to 4.8) or BB% (7.1% up to 12.4%). He's still generally gutted his way through solid outings, but we're still yet to see the ace who roamed the mound last season.

Kendall Graveman, RHP | 58.8%

That's his ground ball rate, which is good for eighth-highest among MLB starters. Graveman absolutely has to keep the ball on the ground in order to succeed, and he's doing that this year after barely reaching 50% grounders last season. He's induced a majority of his batted balls on the ground in three of his four starts so far, and it should come as no surprise that the fourth start was his disastrous three-homer outing against the Tigers on Monday. He's upped his strikeout rate a bit so far as an extra bonus, which may or may not last, but the key is those grounders.

... BUT WAIT! Bonus entry!!

Eric Surkamp, LHP | 10

That's the number of batters he struck out tonight in his first game back in Nashville. His overall line was 7 ip, 2 runs, 10 Ks, 1 BB, 3 hits, on 91 pitches. And that sells him short, as he was tossing a one-hit shutout before allowing two singles to lead off the 8th, then departing and watching the bullpen let both of them score. He's the top backup until Henderson Alvarez is ready to go, so even though he'll probably never be a reliable long-term MLB starter it's nice to see him pitching well while he stays warm in the minors.

Click here to try out FanDuel daily fantasy baseball! New players win cash in their first league or get their entry fee refunded! Offered in partnership with FanDuel. If you're looking at A's starters the next few days: I'd steer clear of Hahn in his debut, but if Hill pitches on Sunday then I'd be all over him against an Astros team that leads MLB in strikeouts.