Mookie Betts was out of the Red Sox lineup on Saturday night, but hopes to miss only a few days with a sore right knee.

Betts had an MRI at Massachusetts General Hospital earlier in the day. No structural damage was found, only swelling.

“Just fluid around there, that’s all,’’ Betts said. “Trying to get it out.’’

Betts said his knee has been bothering him for a few days. He led off Friday night’s game against the Minnesota Twins with a home run but left the game after the top of the fourth inning.

Betts was slow getting to a ball in right field and Brian Dozier took advantage of it and went to second base. Michael Martinez replaced Betts after the inning.

“I just couldn’t run full speed,’’ Betts said. “I didn’t want to make anything worse. Went ahead and was just precautionary about it. Trying to get it before anything major happens.’’

Betts received treatment much of the day and said he felt better than he did when he left Fenway Park on Friday.

“Make sure everything is good and hopefully get back out there,’’ he said.

Manager John Farrell confirmed that the MRI showed no cartilage or ligament issues.

“Day-to-day is the status. It may take a couple for him before he’s back to us,’’ Farrell said. “Everything points to this being a short-term situation,’’ he said.

Betts, an All-Star, is hitting .307 with an .879 OPS. Through Friday, his 221 total bases were the most in the majors. Betts has 79 runs, 50 extra-base hits, 63 RBIs, and 16 stolen bases.

Rapid progress

Craig Kimbrel was on the field early, practicing his delivery from the mound without a ball then throwing to bullpen catcher Mike Brenly while in the outfield.

Kimbrel, out since July 9 with a cartilage tear in his left knee that required surgery, is lined up for 20 pitches in the bullpen on Sunday and theoretically could be activated off the disabled list by the end of the week.

“He feels very good. If he [was] making the ultimate decision medically he’d probably say give me the ball tonight. But we still need to go through the proper steps to get him there,’’ Farrell said.

Kimbrel will need two bullpen sessions then some kind of rehab work, either a simulated game or minor league game, before being activated. The Sox also would want Kimbrel to go through at least one session of fielding practice to test the stability of his knee and how it responds to cutting.

Kimbrel could throw in the bullpen Sunday and Tuesday, face batters on Thursday, and be activated as soon as Saturday. The Sox start a 10-game West Coast trip Thursday against the Angels.

“Whether or not Craig travels with us remains to be seen. He would be getting close to a rehab appearance. Whether it’s a sim game or not, that’s all to be worked out,’’’ Farrell said.

Kimbrel, who was selected to the All-Star team, last pitched on July 6. It should not take him long to get back in game condition as a result. One stint facing hitters could suffice.

“In terms of amount of time missed and the fact he’s able to get aggressive right now in long toss, I would think it will be on the shorter end of number of appearances if it’s even more than one,’’ Farrell said.

‘Hopeful’ on Uehara

It’s not for sure that Koji Uehara will return this season. The 41-year-old righthander, who is on the disabled list with a tear in a pectoral muscle on his right side, had an injection of platelet-rich plasma on Friday to help healing.

Farrell said he was “hopeful’’ that Uehara would return but there was no timetable for when he would start rehab work. It will depend on he is able to regain strength and range of motion.

“It’s too early to tell,’’ Farrell said.

Chris Young (right hamstring), Josh Rutledge (left knee), and Blake Swihart (left ankle) all worked out on the field before the game. Rutledge is the closest to being ready for a rehab assignment.

Remy out

NESN analyst Jerry Remy left the booth in the first inning when a sudden gust of wind knocked a television monitor into his head. Remy was stunned but was not found to have a concussion after being checked out by medical personnel at the ballpark.

He returned home and was replaced for the remainder of the game by Steve Lyons.

It is uncertain how long Remy might be out, but after leaving the park he tweeted that he was fine.

A vote for Ortiz

Ken Griffey Jr., who will be inducted into the Baseball Hall of Fame on Sunday in Cooperstown, N.Y., on David Ortiz: “He was drafted by the Mariners and I got the chance to see him young. He wasn’t Big Papi, he was Thin Papi at that time. To watch him do the things he’s done over the years, he’s become one of the most feared hitters in all of baseball. He’s done an incredible job in that city. Do I think he’s a Hall of Famer? Absolutely. The numbers he’s put up, three titles, the list goes on.’’

Old foes

Rick Porcello starts Sunday against the Twins for the 27th time in his career. He has faced Minnesota more than any other team. “I know them and they know me,’’ Porcello said. “I have no tricks for them. It’s all a matter of executing pitches. It’s a challenge because there’s no margin for error.’’ Porcello is 8-9 with a 3.87 earned run average against Minnesota . . . Dustin Pedroia doubled in the second inning to extend his on-base streak to 26 games . . . The annual Run to Home Base was held Saturday morning. The 9K event benefits the Home Base program started by the Red Sox to benefit veterans with combat stress or a traumatic brain injury. Governor Charlie Baker was on hand to throw out a first pitch along with Sergeant Kurt Power, an Army veteran who survived being shot by a sniper in Iraq.

Nick Cafardo of the Globe staff contributed to this report. Peter Abraham can be reached at pabraham@globe.com. Follow him on Twitter @PeteAbe.