Basically, it involves watching video and doing some exercises.
This could be an issue after the season when Guerrero becomes eligible for free agency. He could insist on going to a club that wants him to play at least most of the games in right field. Running down balls in the gap and unleashing powerful throws have given him a lot of pleasure over the years, and he feels he still can do those things, given the opportunity.
"No, we have not completely ruled that out," manager Mike Scioscia said on Sunday when asked if Guerrero would be seen in right field again this season.
Why would the manager consider taking the risk in the wake of Guerrero's dubious track record in the outfield this season?
"To be able to freshen some other guys up," Scioscia said, referring to regular outfielders Torii Hunter, Juan Rivera and Bobby Abreu. "It adds depth. It would help us in a couple different ways.
"We'll see. Right now, everybody seems to be holding up pretty well."
After Sunday, the Angels have no more games on artificial turf. Scioscia gave Hunter and Abreu days off at Rogers Centre this weekend, but Rivera, swinging a hot bat, was in the lineup for all three games.
Scioscia has Gary Matthews Jr. and Robb Quinlan for outfield depth, and even Chone Figgins in a pinch. Matthews performed capably in Hunter's absence for five weeks. In September, when rosters expand, Reggie Willits, Sean Rodriguez and Terry Evans can be added to the outfield mix if Scioscia desires more depth.
The Angels gave Guerrero two starts in right field this season after he'd recovered from right knee surgery and then a torn pectoral muscle sustained throwing from right field in an exhibition at Dodger Stadium on the eve of the season.
The second start he made in right, at Angel Stadium against the Rangers on July 9, was disastrous. Getting in position to make a throw from right-center, he pulled a muscle behind his left knee -- not the one that was operated on in October -- and went to the disabled list for 25 days.
His start at DH on Sunday is Guerrero's 64th game appearance and game No. 122 for the Angels.
Guerrero needs a big finish to reach 25 homers and finish at .300 or higher for the 12th straight season. Only Lou Gehrig achieved that distinction for 11 consecutive seasons before Guerrero.
With 41 games left before Sunday's first pitch by Jays lefty Ricky Romero, Guerrero needs 14 homers to reach 25. He's batting .303.
Since coming off the DL on Aug. 4, Guerrero is batting .338 with seven homers in 17 games. With 403 career homers and a .322 lifetime batting average, he joins Hall of Famers Gehrig, Jimmie Foxx, Stan Musial, Babe Ruth and Ted Williams as the only players with at least 400 homers and a .320 or higher average.