SAN FRANCISCO -- Astros catcher Jason Castro was unavailable for the first two games of the series against the Giants because he's been feeling discomfort in his right knee, which he seriously injured last spring.
"It slowly built and built and when we were on the break it kind of hit a peak," said Castro, who tore his ACL and had surgery in March 2011.
The Astros may need to make a decision on Castro because if he's unable to catch they have no backup for Chris Snyder, who caught all 12 innings on Saturday night and withstood a jarring home-plate collision on Friday.
Castro said he's not sure whether he'll be able to play on Sunday, for the finale of the series against the Giants.
"It's a day-to-day thing," he said. "It felt better at certain points today than the day before. We just have to watch it on a daily basis."
Prospect Villar breaks hand punching door
SAN FRANCISCO -- Jonathan Villar, the closest shortstop prospect to the Majors in the Astros' system, will miss six weeks after fracturing his right hand punching a door during a Minor League game on Friday night, the club announced on Saturday.
"This is a big loss for us," Astros general manager Jeff Lunhow said. "Jonathan was having an outstanding season and really showed that he is one of the top young shortstops in all of Minor League baseball. The injury is unfortunate for Jonathan, but he has a very bright future ahead of him and we're looking forward to him getting back on the field."
Villar, 21, had 11 homers and 50 RBIs at Double-A Corpus Christi. He entered the season at No. 5 on MLB.com's Top 20 Astros Prospects List, and he was leading the Texas League with 39 stolen bases.
Villar hit a homer to lead off the game and ended the night 1-for-4, playing the entire game. X-rays afterward revealed the fracture, which he suffered punching a door between innings at some point during the game.
Moore's up-and-down career has chance to peak
SAN FRANCISCO -- There are two ways to look at Scott Moore's career. One is that he's been a professional baseball player for 11 seasons, which is no small feat. The other is that he was the No. 8 overall pick in the 2002 Draft, and so far he's bounced among four organizations and never had 100 big league plate appearances in a season.
Moore sees both sides. Although he says he's proud of his career, he also admits that he'd like to establish himself in the Majors.
"I haven't played as much in the big leagues as I'd hoped," he said. "Hopefully this is the opportunity here."
Moore joined the Astros on June 26, and in his 36 plate appearances since then, he's hit .306 with three homers. The Astros say he will be the first baseman against right-handed pitchers, which means he'll be playing most of the time.
"As well as he has swung the bat, he is deserving of that time," manager Brad Mills said. "You'd like guys to deserve the at-bats and playing time and just let them go. Right now, the way he's swinging the bat, he deserves the playing time. We want to be able to give it to him."
Moore, 28, was the first-round pick of the Tigers in 2002. He was traded to the Cubs in 2005, and he reached the Majors with Chicago in 2006. He also played in the Majors with the Orioles. He went back to the Cubs as a free agent in 2011 but never appeared in the Majors. It took him nearly half a season in the Houston farm system before getting a shot when Justin Maxwell got hurt in late June.
He's made the most of it so far, hitting safely in all nine games he's played.
"We have a whole second half to go," Moore said. "Hopefully I can keep it going."
Catcher Jason Castro has been bothered by a sore right knee for the past week, Mills said. Mills said he is hoping Castro can play on Sunday.
Jose Altuve was named the Astros recipient of the MLB Players Alumni Association's Heart and Hustle Award. One player per team is selected for his "passion, desire, and work ethic, demonstrated both on and off the field." The MLB winner will be announced Nov. 13.
Jeff Fletcher is a contributor to MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.