Whether Tucson reliever Brad Boxberger has an effective outing or not typically comes down to one thing: his command.

The 24-year-old right-hander has battled inconsistency finding the strike zone throughout the season. When things are going well, his deceptive delivery allows a low-90s fastball to sneak past bats and keep hitters off balance.

But when Boxberger struggles, he's pitching from behind in the count and leaving fastballs in the middle of the plate.

In five appearances with San Diego this season, Boxberger threw first-pitch strikes to just 43 percent of batters he faced and walked seven in 6 1/3 innings. In Tucson, Boxberger has a WHIP higher than 1.5 despite allowing fewer hits than innings pitched.

"It's all just getting out there and trying to make a pitch," Boxberger said. "Consistency throwing strikes has been the main thing."

Boxberger took a step in the right direction with two scoreless innings in a 6-4 win on Wednesday, allowing two hits without a walk. But the USC product still averages more than five walks per nine innings pitched.

Boxberger's delivery allows him to hide the ball well from hitters and the ball leaves his hand from behind right-handed batters. But that motion can sometimes lead to pulling the ball out of the strike zone despite how comfortable he is with the delivery.

"You have to have a little finer control the higher up (in the organization) you go," said Padres manager Terry Kennedy, adding that he things Boxberger sometimes tries to be too careful around the strike zone instead of attacking hitters.

Making the adjustment to throwing more strikes instead of living on the edges of the zone could be tough for Boxberger. But he said he's now focused on pounding the strike zone and letting things fall into place.

"Sometimes you'll get beat," he said. "But as long as I'm in the strike zone, they'll be swinging and just let the defense do their job."

Inside pitch

• Left fielder Daniel Robertson will represent the Padres at the Triple-A All-Star Game, in Buffalo, N.Y., on July 11. Robertson is hitting .328 with 17 doubles and eight stolen bases.

• Padres general manager Mike Feder said he's hoping an official announcement about the team's future will come during league meetings in Buffalo the week of the Triple-A All-Star Game. The league is ironing out some of the finer details before officially announcing the Padres will return to Tucson for a third year.

• San Diego Padres outfielder Jeremy Hermida arrived in Tucson Thursday and is expected to begin a rehab assignment today.