© 2013 MLB Advanced Media, L.P. All rights reserved.

7/27/2013 12:35 A.M. ET

Martinez goes on DL with sprained wrist

TORONTO -- The Astros placed outfielder J.D. Martinez on the 15-day disabled list following Friday's 12-6 loss to the Blue Jays with a sprained left wrist suffered while sliding into second base in the sixth inning. Outfielder Robbie Grossman was recalled from Triple-A Oklahoma City.

Martinez, who went 2-for-3 with a double and two runs, injured the wrist trying to break up a double play. He is hitting .319 (15-for-47) since July 5 and .256 with seven homers and 36 RBIs this year.

"I just slid and that turf is really hard," he said. "I think I kind of just sprained my hand a little bit."

The Astros are scrambling to get Grossman to Toronto in time for Saturday's 1:07 p.m. ET game against the Jays. He went 3-for-4 for Oklahoma City on Friday night to raise his batting average to .281 in the Minor Leagues this year.

This will be Grossman's second stint with the Astros. He appeared in 28 games in April and May and hit .198 (22-for-111), starting 28 games, before being sent back to Triple-A.

Krauss still getting used to bench role

TORONTO -- Astros outfielder Marc Krauss went from playing every day at Triple-A Oklahoma City to getting sporadic starts since he was called up on June 21 when Trevor Crowe ran into an outfield wall and injured his shoulder.

Krauss made his 11th start of the season on Friday, batting seventh and playing left field. He made his presence felt early, as he hit his second homer of the year, a two-run shot off Toronto starter R.A. Dickey, in the second inning. He added a two-run double in the fourth to match his career RBI total in one night, but the Astros lost to the Blue Jays, 12-6.

Krauss has started seven games in left field, two in right and two as designated hitter, and entered Friday hitting .175 with one home run and four RBIs.

"It's an adjustment, definitely," Krauss said. "It's the first time I've ever been a bench-type guy. It's a different preparation. Every day you've got to prepare like you're in there, even if you're not. I just always do my early work and make sure my swing feels good, because at a moment's notice you could be put in there, and every few days get to start and you have to take advantage of those days."

Krauss has grown a bit more accustomed to the role in the last month, but has yet to find his groove at the plate after hitting .277 with nine homers, 35 RBIs and 43 walks for the RedHawks. Still, he said it's important not to put pressure on himself when he does start.

"I'm excited, definitely, just to get the opportunity to be in there," he said. "Every time you see your name in the lineup, it's exciting. You get to perform and do what you love. I don't really feel the pressure that 'Geez, if I don't do well today, I might not play for a few days.' That's just baseball.

"Sometimes you're going to hit it hard and not get many hits, and maybe get jammed a couple of times and find hits. You really can't control the results. You just have to have a good mindset coming in and control what you can control."

Sparks throws BP in preparation for Dickey

TORONTO -- Astros broadcaster Steve Sparks pulled double duty on Friday.

Sparks, a former knuckleball pitcher who spent nine years in the Major Leagues, dusted off his right arm and threw two rounds of batting practice in the batting cage prior to the game against the Blue Jays, who were starting knuckleballer R.A. Dickey.

The Astros got seven hits and five runs off Dickey in six innings, but lost, 12-6, to Toronto.

Astros hitting coach John Mallee and assistant hitting coach Dan Radison asked Sparks, who's in his first year in the radio broadcast booth, if he would be willing to throw to the Houston hitters.

"I threw two groups to everybody and got them to see a bunch of knuckleballs," Sparks said. "I wasn't watching the ball today, and it didn't feel like a lot of them were coming out of my hand really good, but I think just being able to see the ball dance just a little bit, and how it wouldn't come out like a normal fastball, I think is beneficial for a lot of these guys.

"By the second round when they were hitting off me, I could see some guys were making some good adjustments. I think it paid off, to be honest with you, but we'll see what happens in the game."

Sparks, who last appeared in the Major Leagues with Arizona in 2004, said that during his playing career, the Yankees offered to pay his way to come and throw batting practice to them prior to a playoff game against Boston in which Tim Wakefield was going to pitch.

Sparks declined the offer because he was still an active player and shared agents with Wakefield.

"They said, 'We'll put you up, take care of you. Just name your price,'" Sparks said. "I didn't do it because I felt like I was kind of breaking the code. I can't remember if anybody else has ever asked me to do it, but I felt like now that I'm employed by the Astros, I can definitely do it."

Cosart works on delivery in bullpen session

TORONTO -- It didn't matter that rookie righty Jarred Cosart debuted with two solid starts. There's always room for adjustments, and pitching coach Doug Brocail worked with Cosart during his bullpen session on Friday to get him to square up his shoulders more during his delivery.

"He's got some inversion," Brocail said. "I said, 'Listen, your inversion and your hitch comes from you being across your body and it opens up your chest. Let's erase all that.' I put the rosin bag down [in front of him], which is dangerous, and I said, 'You have to be conscious and I want you to watch your land and then throw pitch."

And the results?

"From the first [pitch] to last -- boom, boom, boom, boom, boom -- great bullpen," Brocail said.

Cosart threw eight scoreless innings of two-hit ball in his Major League debut on July 12 against Tampa Bay, and threw seven innings and allowed one earned run on seven hits and three walks in his next start, Tuesday against the A's at Minute Maid Park. But Cosart, the seventh-ranked prospect in the Astros' system by MLB.com, said he's always willing to get better.

Cosart does throw across his body, which cuts himself off when he's pitching away to right-handed hitters.

"So we were just trying to square me up a little bit and keep me more in line, and it was awesome," he said. "Everything felt smoother, mainly the offspeed pitches. Hopefully I can take it into the next game and see how it feels and keep working on it in every bullpen, and hopefully it helps me have a long career."

Brian McTaggart is a reporter for MLB.com and writes an MLBlog, Tag's Lines. Follow @brianmctaggart on Twitter. This story was not subject to the approval of Major League Baseball or its clubs.