Jeter Downs, acquired in the Mookie Betts trade, has been called up to Boston. Downs, 23, is batting .187 in Triple A over the last two seasons. Elise Amendola/Associated Press

The centerpiece of the Mookie Betts trade is joining the Red Sox – at least for a couple of days.

Boston called up infield prospect Jeter Downs before Monday’s game, the team announced. To clear a roster spot, the club designated recently acquired pitcher James Norwood for assignment.

Downs’ stint in the majors is expected to be a short one. MLB teams are required to cut down the number of pitchers on their rosters to 13 on Monday, meaning the Red Sox needed to replace a pitcher (Norwood) with a position player (Downs) to get from 14 pitchers to 13. Downs is expected to provide infield depth for a couple of days before Christian Arroyo (COVID list) or Kiké Hernández (injured list) is activated. Both players are likely to return before the end of Boston’s three-game series against the Tigers, which begins Monday.

Downs, 23, arrived with much fanfare as one of three players the Red Sox acquired from the Dodgers for Betts and David Price in Feb. 2020 but has struggled offensively in the minors. The middle infielder has hit just .187 with 25 homers and a .637 OPS in 152 games at Triple-A over the last two seasons and is hitting .180 with a .694 OPS in 53 games this year. He is considered a good defender up the middle but will need to improve offensively to get a longer opportunity in the majors. Once one of the top prospects in Boston’s system, Downs is now ranked by SoxProspects.com as the No. 13 overall prospect in the organization.

Norwood was acquired Saturday in a minor trade with the Phillies and was active for Sunday’s game but did not pitch. The Red Sox now have seven days to trade, waive or release Norwood. If he clears waivers, he can be sent to Triple-A Worcester.

Boston now has 39 players on its 40-man roster. Arroyo will claim the final spot when he returns. At full strength, once Arroyo and Hernández return, the Red Sox will have to decide whether to keep Jarren Duran or Rob Refsnyder on their active roster.

FORMER RED SOX utility man Brock Holt is not yet ready to retire, but he is making some future plans for April 2023.

Holt, who was back at Fenway Park over the weekend, told NESN that he is planning on running the Boston Marathon to support the Dana-Farber Cancer Institute next spring. The former Jimmy Fund captain will run alongside his wife, Lakyn.

“The Jimmy Fund is something we’re going to continue to try to be a part of,” Holt told NESN’s pregame show. “I think we’re going to do some shirts again this summer. We’re trying to think of a design, so if anybody out there has a design idea, let us know. We’re going to try to raise some money that way.”

“I’m going to say this on air so I guess it is going to be officially official but me and Lakyn, we want to run the Boston Marathon next year for Dana-Farber,” Holt said. “She was in, I’ve been on the fence. I feel like that’s a cool thing to say, that you’ve done and this city means so much to us. If we can help out and raise some money and run 26.2 miles, we’ll do it. I guess we’ll have some training sessions this summer.”

Holt, who played for the Red Sox from 2013 to 2019, has bounced around in recent years. He played for the Brewers and Nationals in 2020, then the Rangers in 2021, and spent spring training with the Braves this year before being granted his release ahead of Opening Day. Holt has hit .209 with a .572 OPS in 112 games over the last three seasons.