Holt had been called up April 6, but did not get into a game. He was returned to Pawtucket to make room for Roberts, who joined the Red Sox on April 7 as a free agent.
In 12 games with Pawtucket this season, Holt was hitting .380 (19-for-50), with a .446 on base percentage, .600 slugging percentage, 11 runs scored and three RBIs. He had stolen four bases without being caught.
"We felt like we needed to create a little bit of a jump-start to the offense," manager John Farrell said. "With the designation of Ryan, we got another left-handed hitter here in Brock Holt. We've come through a stretch of I think seven left-handed starters against us over the past 10. And we're kind of reversing that right now, going against primarily right-handers. So [I] felt like we needed to try different combinations and to spark that bottom third of the order."
Farrell was pleased with reports he had received on Holt.
"He's clearly earned the promotion here," Farrell said. "When he was sent out even after just one day of being here with the big league club, I think he was initially disappointed. But he's channeled that in the right way and gone out and played very well on the left side of the infield."
In 26 games with the Sox last season, Holt hit .203 (12-for-59}, playing 20 games at third base and five at second.
Roberts had struggled with the Sox. In five games, he was hitless in 11 at-bats, with four strikeouts and two walks.
"He had about a nine-day layoff from the end of Spring Training till he joined us here," Farrell said. "As we talked to him today, he's got to go through the waiver process, but we certainly want him to remain in the organization. [We] feel like he needs at-bats to get things going a little bit."