Alfredo Aceves, Vicente Padilla
Felix Doubront, Andrew Miller, Aaron Cook, Ross Ohlendorf
Alfredo Aceves is the only true lock to make the team, but it's inevitable that at least one or two more contenders and pretenders all land on the Opening Day roster. Aceves has only allowed one run in nine strong innings, striking out nine in the process without walking anyone.
Vicente Padilla is also a strong contender to get the job, pitching in four games this spring, with impressive starts against the Yankees and the Rays. He did allowed four runs on five hits in a two inning appearance against the Pirates, but overall, he's showing that he still has what it takes to pitch in the big leagues.
Felix Doubront got roughed up in a two inning appearance against the Cardinals but did make up for it with a strong four-inning appearance against the Yankees where he struck out four and only allowed two hits.
Andrew Miller has only thrown a total of three innings over two games this spring, while not allowing a hit and striking out five. If he was really in contention, he would have seen more innings this far into camp.
Aaron Cook also hasn't pitched that much this spring, appearing in two games and throwing a total of 5.1 innings. He's only allowed one hit over those innings, walking three and striking out two.
Ross Ohlendorf is a great player to have on the roster but I don't think he'll end up getting the No. 5 spot in the rotation, only throwing 3.2 innings over two games. He has yet to let up a run but has walked three batters.
After seeing all of the pitchers in camp vying for that final spot in the starting rotation, I think it makes the most sense to give the No. 5 spot to Vicente Padilla. He only had one shaky start against the Pirates but his impressive start against the Yankees counteracts that. Alfredo Aceves will be much more valuable in the bullpen, and could be used as a spot starter if need be. In the end, Ohlendorf and Miller will make the team as relievers.