ARLINGTON -- Twins center fielder Denard Span got the night off against the Rangers on Friday, so Ben Revere shifted from right field to center field and Darin Mastroianni got the start in right field.

Mastroianni has seen more playing time recently, as it marked his fifth start in the last week after playing sparingly throughout most of June.

He's taken advantage of it by hitting .429 with six stolen bases dating back to Saturday's doubleheader against the Royals.

"He's pretty fun to watch," Twins manager Ron Gardenhire said. "He's very entertaining on the basepaths. He looks for openings, he can take advantage, he can outrun some things. I like to see him in there."

Stealing bases is nothing new for Mastroianni, who stole as many as 70 in a season as a Minor Leaguer while in the Blue Jays organization. He has eight stolen bases in nine tries this year after stealing three bases against the Tigers on Thursday.

"I take a lot of pride in it," Mastroianni said. "Speed has always been a big part of my game. I've always been a pretty good basestealer throughout my career in the Minor Leagues. I've learned a lot over the years."

Mastroianni said he studies the pitcher and catcher every game whether or not he's playing to try to give pointers to his teammates about whether they'll be able to steal. He added he stands in the same spot in the dugout every game to get the best angle to watch the pitcher.

"Just because you're on the bench doesn't mean you're useless," Mastroianni said. "It's my way of trying to help the team even when I'm not playing."

Twins glad Nathan has found success in Texas

ARLINGTON -- The Twins made their first trip to visit the Rangers this season on Friday, which also gave them their first chance to see former Minnesota closer Joe Nathan at Rangers Ballpark.

It wasn't the first time they saw Nathan, however, as the Twins hosted the Rangers at Target Field from April 13-15, and Nathan tossed two scoreless innings against his former club.

Nathan, who is the Twins' all-time leader in career saves with 260, has been a solid pickup for the Rangers this season, as he has 18 saves with a 1.87 ERA, 42 strikeouts and four walks over 33 2/3 innings, earning a berth on the AL All-Star team.

It's been a big improvement for Nathan, who posted a 4.84 ERA with the Twins last season after missing the 2010 campaign following Tommy John surgery.

"His velocity has come back," Twins manager Ron Gardenhire said. "He went through some tough times last year where he couldn't get the ball where he wanted. But he kept working at it. And finally some good things have happened. He's a class act. He's a heck of a reliever and a heck of a pitcher."

Nathan showed signs last year that he was turning the corner, considering he posted a 3.38 ERA after returning from a stint on the disabled list in late June.

But this year, he's an All-Star for the fifth time in his career, and Twins co-closer Glen Perkins said he was happy to see it.

"He's having a great year," Perkins said. "He was probably the one guy I was excited to see, because I've learned a lot from him. It was tough at times last year watching him with all the success he's had struggle. So I'm glad that he's been able to get back."

Deduno pumped to make first big league start

ARLINGTON -- Right-hander Samuel Deduno joined the Twins on Friday after having his contract selected from Triple-A Rochester, and said he's excited to make his first big league start on Saturday against the Rangers.

Deduno has some Major League experience, with a career 3.18 ERA in a combined 5 2/3 innings with the Rockies (2010) and Padres ('11). But this will be the first start for him after he posted a 2.14 ERA with 46 strikeouts and 22 walks in 42 innings with the Red Wings.

"It's a good chance for me," Deduno said. "When I was in the big leagues before I didn't pitch much. So it's a good opportunity."

Deduno said that despite his high strikeout rate in the Minors, he doesn't overpower batters with his fastball, as he's more known for his offspeed pitches.

"I'm not really a power pitcher," Deduno said. "But I have a pretty good curveball and a pretty good slider. My changeup is pretty good, too. My fastball moves a lot and it's been around the plate. So it's been good enough."