Victorino has played seven games in the first nine days since coming off the disabled list last week, including both ends of a day-night doubleheader versus Tampa Bay on Thursday and all of a three-hour, 37-minute game against Oakland on Friday.
"Still looking at the shortened spring training, the number of games missed coming out of the start of the season," manager John Farrell said. "He's available for defense or pinch-hitting duty later today, and will be back on the field tomorrow."
Victorino's absence prompts Farrell to shuffle the positioning in the outfield. Jackie Bradley Jr. will start in right field for the first time since April 8, while Grady Sizemore will start in center for the first time since April 20. Bradley has been very good defensively as the regular center fielder, and Farrell wants to keep his glove in an important spot.
"The arm strength of Jackie in right field is a factor in that and we still feel like right field might be the most important position in this ballpark, so his range lends to that," Farrell said.
Bradley enters Saturday as one of five American League outfielders with three assists.
In other pregame news:
Red Sox right-hander Edward Mujica was hit hard again in a one-inning stint during Friday's 7-1 victory, allowing two hits and more than one hard out. Mujica, expected to be a piece of the late-inning formula for Farrell, has given up 10 runs on 16 hits and four walks in 10 innings so far, and has seen lower-leverage situations as his struggles have continued.
"The arm strength is increasing, we're seeing better velocities," Farrell said. "There's been a few things at play here. Arm strength is increasing. His command has been a little bit less than what it was a year ago just by the number of walks he's issued already."
Mujica's average fastball velocity was a shade over 90 mph in his first few outings, then sat around 92 for a handful of appearances before topping out at 93 against Tampa Bay earlier in the week. His splitter also topped out versus the Rays and his little-used slider has inched up as well, coming in at a season-high average of 87.6 mph on Friday.
Farrell noted Mujica's open delivery and said that the one-time St. Louis closer is working on an adjustment that would provide more deception. That effort, along with the apparent increase in arm strength, may yield more important outings in the near future.
"Edward's going to be critical for us. He and [Craig Breslow], getting back in the mix more consistently," Farrell said. "We're going to need those two guys to spell others and allow for proper rest for the entire relief group."
Breslow, arguably the most important reliever behind Koji Uehara last year, has surrendered six runs with five walks in seven innings so far.