MESA, Ariz. - The competition for the A's fifth starter spot will be an interesting one, with several candidates offering their own unique stories.
That's likely to be the only suspense regarding Oakland's rotation, as manager Bob Melvin strongly hinted that Jharel Cotton will be his No. 4 starter.
"On the talent level and what we saw last year, there's probably a leg up," Melvin said following Thursday's workout. "We want him to go out there and fight for a job, but he definitely impressed us last year."
Cotton posted a 2.15 ERA and an excellent 0.818 WHIP over five starts in his September call-up, showing nice command of a variety of pitches in his major league debut.
Who rounds out the A's rotation is tougher to handicap. Andrew Triggs, who made his big league debut last season at age 27 and endured eight trips back and forth between the majors and minors, is a strong candidate. On Thursday, Raul Alcantara and Jesse Hahn also earned praise from Melvin.
"We were impressed with what (Alcantara) did last year," Melvin said. "He seems to get more comfortable in big league camp. He threw a really good bullpen today."
Alcantara, who like Cotton got his first taste of the bigs in September, went 1-3 with a 7.25 ERA in five starts. Those numbers don't reflect the high ceiling that the A's feel the right-hander has. Adding intrigue to his case: Alcantara is out of minor league options, meaning if the A's wanted to send him down, they would first have to run him through waivers and risk losing him to another team.
[GALLERY: A's 2017 spring training]
Melvin on Thursday mentioned Alcantara, 24, could also be considered for the final bullpen spot based on his potential as a long reliever.
Hahn, who was a regular in the 2015 rotation, is looking to rebound after a disappointing 2016 season.
"Jesse Hahn looked like he has his sinker back, and that really is the difference for him," Melvin said. "Last year, his velocity was up but the sinker wasn't there for him."
PROSPECT WATCH : A.J. Puk, the 6-foot-7 lefty who the A's drafted with the sixth overall pick in June, got on the mound for the first time in camp and showed why some had him rated the top overall prospect in the draft.
"Early in spring you're looking for fastball command, and he had command of that," Melvin said. "He showed a good changeup. I know his breaking ball came a long way last year. He's one of those guys that's free and easy. He's closer to you once he releases the ball (because of his height) and he's got good life on him. It's a good start for him to have a good showing in his first bullpen."
Puk won't challenge for the big league roster. The A's like to get the previous year's top pick in camp to experience the big league environment, but he'll likely begin this season at either low or high Single-A. Last season, he posted a 3.03 ERA in 10 starts for Vermont, the A's short-season A squad, and struck out 40 in 32 2/3 innings.
NOTEWORTHY: A storm is moving in from Southern California and expected to hit the desert this weekend, putting Sunday's first full-squad workout in jeopardy. That wouldn't be such a terrible thing for the pitchers, who would be scheduled for an off-day from mound work Sunday anyway. But as Melvin mentioned, "with everybody here, we'd like to get the full day in."
A large number of position players already have been on the field for informal workouts, and the A's may try to cram more activity in Saturday with the anticipation that Sunday may be abbreviated.
FAMILIAR FACE: Former A's first baseman Scott Hatteberg, a special assistant to the baseball operations department, has been in uniform and once again is helping out in spring camp.