He threw nearly 50 pitches two days before. It was the second inning, and Ryan Castellanos wasn’t even wearing cleats.

To his surprise, the freshman was called into the game last weekend when Illinois played Missouri at Busch Stadium. The appearance started the best week in Castellanos’ young college career and has propelled him into the regular starting rotation for Illinois.

The game’s starter, Rob McDonnell, had to come out of the game with arm soreness after the first inning and Illini head coach Dan Hartleb called on Castellanos, who only had time to throw about five warm up tosses, mainly because he spent the rest of the time trying to find his shoes.

College baseball has a rule that a pitcher can take as much time as he needs to warm up on the mound when he enters a game, a rule Castellanos said he’s definitely thankful for now.

He settled in and gave the Illini three innings they needed to preserve the bullpen while allowing just one run and striking out three.

That earned him a start this past Sunday, where he got his first collegiate victory, stopping Indiana’s 18-game winning streak. In six innings, he surrendered five hits and didn’t walk a batter. He doesn’t walk many, only just four in 17 1/3 innings this season.

Hartleb called his performance “outstanding” before naming him the team’s Sunday starter, a spot that had been split between two other freshmen, Kevin Duchene and Nick Blackburn.

Castellanos isn’t overpowering and doesn’t strike out many batters, but said he likes to rely on his defense to make plays behind him.

The right-hander from Davie, Fla., is 1-0 with a 2.60 ERA.

He still talks everyday with his brother, Nick,who is the top prospect in the Detroit Tigers organization and is the No. 21 overall prospect in the minors by Baseball America and MLB.com. Nick is currently playing for the Tigers’ Triple-A affiliate, the Toldeo Mud Hens, and will almost certainly be called up at some point this season for his major league debut. Right now, Castellanos has plans to play summer ball in Toledo near his brother.

Two-headed monster

It wasn’t a save situation, in fact, the score was 8-1 when Reid Roper pitched a scoreless ninth inning this past Tuesday against Eastern Illinois. It was Roper’s first appearance on the mound since March 18 against Southern Illinois. Roper does double duty for the Illini, serving as the team’s second baseman and closer, with five saves on the season.

His workload has decreased recently with the emergence of Bryan Roberts as a dominant setup man. Roberts has yet to allow a run in 10 innings this season.

Hartleb has been able to keep Roberts in to finish off games, keeping Roper’s arm fresh whenever he is needed or to use Roper when he wants to give Roberts a rest.

“It’s kind of a two-headed monster for us and a luxury,” Hartleb said. “So we’re very confident in who we bring in late.”

Roper’s infrequent outings have also been the result of some injury issues for Illinois.

Him pitching on Tuesday made for an unusual defensive alignment when David Kerian, who is team’s normal first baseman, but actually started the game in left field, came in to play second base during the ninth.

Freshman and backup middle infielder Adam Walton broke his finger and is expected to miss an extended period of time. Walton has appeared in 11 games for the Illini this season including four starts. He was hitting .222 with an RBI, but has walked six times on the season for an on base percentage to .417.

The other alternative at second base is Michael Hurwitz, but he is the Illini’s usual designated hitter.

Right fielder Davis Hendrickson was a late scratch before Tuesday’s game because of an eye injury. He was hit in the face with a line drive this past Saturday, but he did play Sunday. Hendrickson was removed from the starting lineup just minutes before the game started because the Illini wanted to use caution.

“I think Hendrickson’s going to be OK,” Hartleb said. “He has a little bit of an infection from the injuries this past weekend, but he’ll be fine. I’m never going to put anybody on the field if we think there’s any chance that it could be detrimental to their health.”

Healthy in the standings

The Illini can now refocus on the Big Ten schedule this weekend when Purdue comes to Illinois Field. The Boilermakers spent most of last season running away with the Big Ten regular season and tournament championship, with a record of 17-7 in conference, including a sweep of Illinois.

Purdue entered the season needing to replace seven different starters from last year’s lineup, and enter this weekend with a 4-5 conference record.

Hartleb said this is a chance for the Illini to start getting “healthy in the Big Ten standings,” as they enter this series with a record of 2-4. The Illini have already played Indiana and Nebraska, the two teams picked in the preseason by the Big Ten coaches to finish first and second, respectively.

“I think we should be up toward the top of the standings,” Hartleb said. “I do feel like we should be at the top one, two or three in the conference, and playing those tough people early helps as we move forward.”

Jamal can be reached at [email protected] and @jamalcollier.