Indians pitching coach Mickey Callaway said the team has only one goal in mind for Pestano.
"I just think he needs to get his confidence back," Callaway said. "It seems like when he's out there right now, he just doesn't have that confidence that he once had. Whether you have good velo or bad velo, or good pitches or bad pitches, if you don't have any confidence, it's going to be tough to succeed.
"He'll go down there, get his innings in, get his work in and try to build that confidence back up, so whenever he comes back, whatever his velocity is, whatever pitches he has, however they're working, he can have confidence to go out there and get outs."
Through three appearances this season, Pestano allowed six runs (four earned) on eight hits in just 2 2/3 innings, during which he struck out four, walked one and yielded one home run. The right-hander's average fastball velocity to date has been 88.7 mph, which is down from 92.1 mph last season and 91.8 mph in 2012.
Pestano took over in the ninth inning of Tuesday's win over the Padres with an 8-3 lead, but he surrendered three runs (only one was earned due to a fielding error by first baseman Nick Swisher). San Diego's late push was ignited by a long leadoff home run to center field by Xavier Nady.
"I just think when he makes a mistake right now, he's paying for it," said manager Terry Francona, who added that he feels too much is made of pitch speed. "I don't think I'm real comfortable coming in every night talking about somebody's velocity.
"I think early in camp, he looked like he was eating up hitters. It was the same velocity he was now. He had really good movement, and he was getting in on lefties. Right now, he's just leaving some balls over the middle."
The 27-year-old Lee rejoins the Indians after serving as the 26th man for the team's doubleheader on the road against the A's on April 2. Lee did not pitch that day, but he did post a 4.15 ERA in eight appearances (4 1/3 innings) with Cleveland last season. This spring, the sidearmer had a 3.24 ERA with 12 strikeouts and five walks in 8 1/3 Cactus League innings.