SAN DIEGO - First baseman Mitch Moreland left Tuesday's game in the second inning with a strained left hamstring. He is scheduled for an MRI Wednesday morning, and says he will know more about his prognosis following the test.

Michael Young came on to replace Moreland after the 26-year-old tweaked the hamstring running out what would become an inning-ending double-play ball.

"The first time I felt it was when I hit the base, I was trying to lean forward," Moreland said. "Don't really know a whole lot right now, we have the MRI scheduled ... and we'll go from there."

Manager Ron Washington said before the game that he planned to play Moreland in one of the final two games of the Padres series to spell a struggling Young. Washington said Young was more comfortable playing Wednesday to avoid two consecutive days off with an off-day Thursday, and so Moreland got the start in Tuesday's game.

After the game, Washington said that the team plans to fill in for Moreland with a combination of Young, Mike Napoli and Brandon Snyder -- in other words, pieces that are already in place.

Hamilton returns to Rangers lineup

SAN DIEGO -- Josh Hamilton returned to the starting lineup Tuesday night against the Padres after battling a stomach virus since last Thursday.

The virus, which forced Hamilton to be hospitalized for part of Friday, cost the league's RBI leader four games and 10 pounds off his normal playing weight of 230.

Hamilton saw action in Monday night's series opener, entering to play the outfield in the ninth inning. According to manager Ron Washington, Hamilton would have hit had the pitcher's spot come up again.

"I'm probably about 80-85 percent, which is good," Hamilton said. "I'm feeling better, strength's coming back."

The virus worked its way through Hamilton's family, and he says his 3-year-old daughter, Michaela Grace, is still battling its effects. But Hamilton says the virus has "run its course" for him, and he has no concerns about playing tonight.

Darvish focusing on commanding pitches

SAN DIEGO -- Rookie phenom Yu Darvish (8-4, 3.57 ERA) is set to take the mound in the Rangers' series finale with the Padres tomorrow afternoon at Petco Park. Darvish, who was nearly unhittable to start the season with a 2.18 ERA in his first six starts, is just 4-4 with a 4.53 ERA over his last eight outings. But the righty regained his early-season form in his last outing, an eight-inning, two-run performance against the Astros on Friday.

"I think command was better last outing," Darvish said. "The feel of the ball, the way it's coming out of my hand, it feels good."

Rangers manager Ron Washington agrees that Darvish's troubles were a product of the inability to spot his fastball.

"You look back at those outings, he was erratic with his command," Washington said. "Speaking with him, it was mechanical. He worked on his mechanics ... the key right now is just that he keep throwing strikes and he trust his fastball."

Darvish threw a bullpen Monday in preparation for Wednesday's start, his first against the Padres. He faced San Diego in Spring Training, but Darvish says he'll learn more from studying video of Padres hitters this week than he can glean from a Spring Training start.

Whatever the specifics of his approach to Padres hitters, Washington hopes to see his young star not only establish his fastball, but do it aggressively.

"What happened the other day is he began to turn that corner and trust his stuff ... he went out there and loaded up the strike zone with his other pitches, too, but he pitched off the fastball," Washington said. "Attack, trust his defense, trust his stuff. That's all he's gotta do."

Perez delivers strong outing for Round Rock

Martin Perez, winless in his last six starts for Triple-A Round Rock, delivered his best performance of the year on Friday.

Heading into his most recent start, Perez, 21, was 0-3 with a 7.48 ERA in his last six outings, as Round Rock lost each of those games. But the southpaw rebounded Friday against Oklahoma City, the Astros' Triple-A affiliate, tossing seven scoreless innings in a 2-0 victory. Perez allowed only one hit, struck out five and walked five while throwing 61 of his 101 pitches for strikes.

"I think the problem I've had in the last month is my mind. I was thinking too my much," Perez said. "Before the last start, I changed my routine before the game. I threw more in the bullpen and long-tossed for about 10 minutes. I threw my fastball in. When I have good command in, I can go to both sides with my offspeed pitches. That's what I'm going to try to do from now on."

Perez was one of a few pitchers that the Rangers likely considered to fill the spot in their rotation left vacant by injuries to Derek Holland and Alexi Ogando. Justin Grimm eventually got called up from Double-A Frisco and earned a win in his Major League debut in Saturday's 8-3 win over the Astros.

"I'm happy for him because he's my friend," Perez said. "When you're not doing good and other people are doing good, you can't think anything bad about them. I saw him the other night, he was throwing really good. I just want to come in here and work hard every day. That's my mindset."

The Rangers' second-best prospect, according to MLB.com, Perez proved Friday why he's regarded as one of baseball's top Minor League players. He lowered his ERA from 5.40 to 4.90 Friday and has posted a 4-5 record this year, striking out 45 and walking 36 in 14 starts.

"In this game nothing is easy," Perez said. "Sometimes I try to throw the perfect pitch. And you can't throw the perfect pitch. That's what I was thinking my last start."

Reliever Cotts makes long trek back from injury

Neal Cotts has been through a lot the last three years.

A World Series champion with the White Sox in 2005, Cotts had Tommy John surgery in 2009. While recovering, he suffered a torn labrum in his hip that also required surgery. That resulted in an infection that forced Cotts to undergo three more surgeries and miss all of the 2010 season. He didn't play in 2011 after being released by the Yankees, but was invited by the Rangers to their Minor League camp this spring.

"The Rangers decided to take a chance. I'm not sure why," Cotts said. "I really had no options. Nobody gave me a job. I'm just trying to make the most of the opportunity. I know I was grateful to get it."

Cotts, who previously considered retiring, performed well enough in Minor League camp to get moved up to the Rangers' big league camp during Spring Training, posting a 4.22 ERA in nine appearances, striking out seven and walking three. He didn't allow a run in his last four outings, becoming a candidate to make the Rangers' 25-man roster. But he suffered another setback, straining a lat muscle as rookie Robbie Ross earned a spot on the Rangers' Opening Day roster.

"It was definitely frustrating," Cotts said. "I went into the spring with no expectations. I thought I competed pretty well during the spring. Stuff happens. You just have to roll with the punches."

Cotts is finally back on the mound, making three appearances so far this season, allowing one run in 3 1/3 innings while striking out five and walking three for Triple-A Round Rock.

"Physically, I feel good," Cotts said. "My location's been a little off in the first two outings. The pitches are there but there's been a couple walks and I've been fallen behind people. Other than that, health-wise, I feel good."

A native of Illinois, Cotts played at Illinois State and spent four seasons with the White Sox, followed by three more with the Cubs. He hasn't been in Texas long, but he's enjoyed his time in the Lone Star State.

"I like it so far," Cotts said. "It's a little warm but the facility here is beautiful. I've only been here about five days. So far, so good."

Short hops

• The Rangers released outfielder Brad Hawpe from Double-A Frisco at his request on Tuesday. The 32-year-old, who had Tommy John surgery in August, never appeared in a game for the Rangers. He played parts of the last nine seasons in the Majors with three different teams; the Rockies, Rays, and Padres.

According to a spokesman for the Rangers, Hawpe did not believe he was close to ready to make a Major League roster, and felt he was taking a spot that could be put to better use for the organization. Hawpe's last full season came in Colorado in 2009, when he hit .285 with 23 homers and 86 RBIs.

• Washington has yet to announce a starter for Friday's series opener with the Rockies in Arlington. Potential candidates include rookie Grimm, who won his first Major League start against the Astros Saturday, and veteran Roy Oswalt, who started for Triple-A Round Rock on Sunday.

• A group of Rangers players headed out to San Diego's Naval Base to watch Navy SEAL training Tuesday morning. Said infielder Michael Young, "it was a great experience, we had a blast."