Pitching for Triple-A Pawtucket, the right-hander struck out the side around one walk in his single inning of work, throwing 19 pitches.
Eovaldi is expected to rejoin the team and work out of the bullpen during Boston's upcoming weekend series against the Baltimore Orioles.
The 29-year-old has been sidelined since April 17 with an injured throwing elbow. Eovaldi posted a 6.00 ERA over four starts to kick of the 2019 campaign.
Last year, Eovaldi played an integral role with the Red Sox en route to their World Series victory after being acquired midseason from the division-rival Tampa Bay Rays. Over 22 1/3 innings in the postseason, Eovaldi authored a 1.61 ERA and 2.71 FIP while working as a swingman.
After becoming a free agent, the Red Sox re-signed the right-hander to a four-year, $68-million deal.
"It's very significant," manager Alex Cora said regarding the impending return of Eovaldi, according to Browne. "That's one more arm, and there's a few more guys that have thrown the ball well, too. You've got (Josh Taylor) and you've got (Brandon Workman) and you've got (Matt Barnes) throwing the ball better. You've got Nate. It's kind of like the domino effect, like, one more guy is going to help us get the previous inning and the previous inning and the previous inning but everything starts from the first inning."
Currently in third place in the Al East, the Red Sox are three games back of the second wild card, which is currently held by both the Cleveland Indians and Oakland Athletics. Boston's bullpen sits in the middle of the pack in the American League in both ERA and FIP.