BOSTON — Willi Castro made his professional pitching debut on Thursday, an assignment, Twins manager Rocco Baldelli said, that was borne of a bullpen session during spring training.

Apparently, he's not kidding.

"I was highly impressed by his bullpen session in Fort Myers. And that's actually true," Baldelli said. "I watched him pitch at least 10 eephus pitches in a row and the catcher's glove didn't move."

They're actually "cutters," Castro said of the 45-mph-or-so pitches that he used to get Kiké Hernández, the only batter he faced, to ground out in the eighth inning.

"I was a pitcher when I was probably 11 or 12, in Little League and travel ball," said Castro, a native of Puerto Rico. In spring training, the Twins asked both him and Nick Gordon to throw a bullpen session so the team could judge whether they could fill in in blowout games. It's a duty Gordon handled four times last season.

"I felt pretty good, lobbing the ball in there and sometimes throwing harder, you know, to surprise the batter," said Castro, who also played six innings at third base and two at shortstop during the game, and hit his first home run as a Twin. "They told me I might get to pitch if we needed it. I was glad to help the team."

Polanco nears return

There could be a few adjustments to the Twins' roster this weekend, including a much-anticipated return.

Jorge Polanco, whose preparations for the season were slowed by knee soreness during spring training, could be activated as soon as Friday, Baldelli hinted.

"He's getting pretty close," Baldelli said. "We'll huddle up [Friday] with Nick [Paparesta, the team's head athletic trainer] and Derek [Falvey, President of Baseball Operations] and see what we're going to do."

Polanco will play second base on most days once he returns, which could mean rookie second baseman Edouard Julien, who homered twice on this trip, returns to Class AAA St. Paul in order to keep playing every day.

Pitching moves will be considered, too, especially after the Twins needed six innings of relief on Thursday. They have no days off until their 10-day homestand ends, so Baldelli clearly wants fresh arms, perhaps both starters and relievers.

Bailey Ober is a likely option if the Twins decide to give the rotation an extra day off, as they are trying to do frequently this year. And another reliever, particularly one who can give them more than one inning, could be added to protect the arms during this long stretch of games.

Farmer guts it out

Kyle Farmer isn't ready to resume playing again, just eight days after being smashed in the mouth by a Lucas Giolito pitch, but he's working toward it. The backup infielder worked out at Target Field on Thursday, his first step toward a return.

"I hear he's got a lot of jokes. Normally, people act the way they feel, so I think he's really beginning to feel better and better," Baldelli said. "He still has appointments he needs to take care of … but he's feeling very well."

Farmer is wearing protective gear on his front teeth, which were displaced by the pitch, but he's no longer on a liquid diet, the manager added. But it's still too early to know how long he might be out.

"It's always going to be more of a mental test than the physical part of it. Yes, there's going to be some pain and some associated throbbing and uncomfortable things," Baldelli said. "This isn't something we're going to be pushing him on. This is something he'll have to convince us that he is good, and that's when we're going to move forward."

Max's mistake

Thursday's game ended with an embarrassing mistake for the Twins. With the bases loaded and two outs, Julien drove home the Twins' fifth run on a single to center. But Max Kepler, who was on second base, rounded third and headed home. But he suddenly stopped and went back to the bag, too late to avoid being tagged out by third baseman Christian Arroyo.

"Kep thought he was just scoring easily on the play. He didn't even think there would be a throw," Baldelli explained. But third base coach Tommy Watkins "had held him up because we're basically going base-to-base since none of those runs actually matter. I think Max was surprised, and once he went too far and stopped, he was out. That was a play I had not seen before in that situation, and hopefully I don't see it again."

Kirilloff helps Saints

Alex Kirilloff hit a two-run double in the third inning, leading the St. Paul Saints to a 5-4 victory over the Scranton/Wilkes-Barre RailRiders on Thursday night at CHS Field.