ARLINGTON, TEXAS - Many major league teams are using the All-Star break to rest pitchers about whom they have workload concerns. The Twins are one of those teams.

Lefthander Scott Diamond, who has come out of nowhere to become the best starter on the staff, will be pushed back toward the end of the rotation after the All-Star break. Right now, it looks as if he will start next Monday against Baltimore, giving him 10 full days of rest between starts.

"We're mindful of protecting him," manager Ron Gardenhire said. "We're going to give him plenty of days before we start him in the second half after the break."

There have been no hints of anything physically wrong with Diamond, who is 7-3 with a 2.62 ERA since being called up from Class AAA Rochester on May 7.

Diamond has thrown 79 innings for the Twins and 34 2/3 innings for Rochester, giving him 113 2/3 for the season. He threw 162 innings between the two stops last season.

By the way, Diamond was 5-19 in 2011 between the Rochester and the Twins, so this truly is quite the turnaround.

"He's a guy who's going out there and giving us six, seven, eight innings every time out, so we're giving him almost an extra break," Twins Assistant General Manager Rob Antony said. "Somebody's going to go 10, 12 days in between starts. So I think they believe it can be a benefit to him and won't hurt him."

As of now, lefthander Francisco Liriano is scheduled to start on Friday against Oakland, with Saturday's starter to be announced and lefthander Brian Duensing set to start on Sunday.

Walters' slight setback Righthander P.J. Walters (shoulder) experienced soreness after his rehabilitation outing on Friday for Rochester. It's not considered serious, but it's enough to rule him out of being activated for the Athletics series.

Walters is expected to start one more time for Rochester by the end of the week, but he will fly to the Twin Cities before that to be checked out.

"The plan is hopefully he'll be ready to pitch again Thursday down in Rochester," Antony said. "He felt fine after throwing but today it felt like less than a bee sting. He just felt something. I don't think they're too concerned about it."

Down to the wire The deadline to sign players selected in last month's first-year player draft is 4 p.m. Friday. So far, the Twins have signed 23 of their 43 selections.

Twins scouting director Deron Johnson said the club is still looking to sign more picks before the deadline. Their top target is ninth-round pick L.J. Mazzilli, a second baseman out of the University of Connecticut. The recommended bonus for that spot in the draft is $130,000. Mazzilli, the son of former major leaguer Lee Mazzilli, might be looking for more.

Blackburn strong Nick Blackburn pitched eight shutout innings for Rochester on Sunday in his first outing since being sent to the minors. The righthander scattered nine hits with no walks while striking out two in a 1-0 victory over Lehigh Valley.