Fitts (arm) was diagnosed Tuesday with inflammation in his brachial plexus following an MRI, Tim Healey of The Boston Globe reports.

According to Healey, the brachial plexus, is a bundle of nerves that begin in the spinal cord and extend through his shoulder and arm, and the finding from Fitts' MRI weren't anything unexpected. The Red Sox aren't yet putting a timeline on Fitts' return, as the team will wait and see how he responds to rest and treatment before clearing him to start throwing again.

Red Sox manager Alex Cora said that Tolle will start Friday's game against the Diamondbacks in Arizona, Gabrielle Starr of the Boston Herald reports.

Tolle would have been available to take the hill Wednesday against the Guardians on four days' rest, but because he's received at least five days of rest ahead of every appearance this season, the Red Sox weren't yet ready to deviate from that plan. Cora said that the Red Sox envision Tolle continuing to start games in September, so it looks like he'll be a regular part of the rotation moving forward after turning in a promising MLB debut this past Friday against the Pirates. In that outing, Tolle punched out eight batters and induced 14 swinging strikes on 84 pitches while limiting the Pirates to two earned runs on three hits and two walks over 5.1 innings.

May will work in relief behind opening pitcher Brennan Bernardino for Wednesday's game against the Guardians, though manager Alex Cora said that the right-handed May will be available for up to 40 pitches, Tim Healey of The Boston Globe reports.

Since May will be pitching on three days' rest after most recently starting in last Saturday's 10-3 loss to the Pirates, he'll face a tighter restriction than if he were operating as bulk reliever on normal rest. Cora noted that the Red Sox aren't yet preparing for May to move to the bullpen on a permanent basis, as the 27-year-old is still likely to make a start during next week's series versus the Athletics. Since being acquired from the Dodgers at the trade deadline, May has produced a 5.68 ERA, 1.70 WHIP and 25:11 K:BB in 25.1 innings through his first five outings with the Red Sox.

Triple-A Worcester manager Chad Tracy said Wednesday that Harrison is tending to an ankle injury, and the southpaw is without a clear timeline to resume pitching, Katie Morrison-O'Day of MassLive.com reports.

The southpaw had recently joined the Red Sox in Boston and appeared to be in consideration for a start Wednesday against the Guardians, but the big club will ultimately have lefty Brennan Bernardino serve as an opener in front of bulk reliever Dustin May in that contest. Harrison's ankle injury may have played a part in him being bypassed for the start with Boston, and it's yet to be determined whether the issue will result in him landing on Worcester's injured list.

Taillon (groin) will begin a rehab assignment with Triple-A Iowa on Thursday, Andy Martinez of Marquee Sports Network reports.

It should be the only rehab start Taillon requires before he rejoins the Cubs' rotation next week in Atlanta. The veteran right-hander has been sidelined for the past two weeks with a left groin strain. When Taillon does return, he'll likely push Javier Assad to a long-relief role.

The Rays promoted Urbina from Single-A Charleston to High-A Bowling Green on Wednesday.

Urbina needed a couple years in pro ball to harness his stuff, but he's broken out this season as a 19-year-old at the Single-A level. He logged a 2.05 ERA, 1.06 WHIP and 96:30 K:BB in a career-high 92.1 innings across 19 starts.

Sasaki (shoulder) struck out two batters and allowed four earned runs on three hits and two walks in his rehab start Tuesday with Triple-A Oklahoma City. He also hit a batter.

Though the 69 pitches (42 strikes) that Sasaki threw marked a slight step back from the 75 pitches he tossed his last time out Aug. 26, he was more efficient, which enabled him to reach five innings for the first time in four rehab outings. The right-hander wasn't quite as sharp as the Dodgers had likely hoped, however; two of the three hits he gave up left the yard, and he now owns an unremarkable 8:8 K:BB over 14 innings on the farm. The Dodgers are letting Sasaki get stretched out as a starter, but the big club wouldn't appear to have an opening for him in its six-man rotation. If Sasaki bypasses another rehab start and gets activated from the 60-day injured list, he could be deployed out of the bullpen.

Sheehan will start Wednesday's game in Pittsburgh, Bill Plunkett of The Orange County Register reports.

Shohei Ohtani had initially been listed as the Dodgers' starter, but Ohtani will instead serve only as the team's designated hitter Wednesday. Manager Dave Roberts had said previously that Sheehan's turn in the rotation would be skipped, but the plan evidently changed. Roberts should offer more clarity behind the decision later Wednesday.

The Red Sox are not planning to recall Harrison from Triple-A Worcester prior to Wednesday's game versus the Guardians, Alex Speier of the Boston Globe reports.

Previous reports indicated that Harrison was headed to Boston and could start Wednesday's contest. However, the club has since announced that Brennan Bernardino will open the contest, with Dustin May slated for bulk relief. Harrison could still get an opportunity with the Red Sox at some point this month, but he'll remain with Worcester for now. The lefty has posted a 3.65 ERA and 48:26 K:BB over 49.1 innings covering 11 starts with Worcester after being dealt to Boston in the Rafael Devers trade.

Martinez retired the lone batter he faced in relief and collected his second hold of the season in Sunday's 7-4 win over the Cardinals.

Martinez had made four straight appearances as a starter from Aug. 9 through Aug. 26, but his last two outings have come out of the bullpen. Though the Reds scratched Nick Lodolo (illness) ahead of Tuesday's 12-9 loss to the Blue Jays, Martinez wasn't called upon for a spot start, as Cincinnati instead had Scott Barlow open the contest before he was followed by five other relievers. Cincinnati could consider moving Martinez back into the rotation if Lodolo ends up requiring a stint on the injured list, though the expectation at this time is that Lodolo will be ready to go the next time the Reds need a fifth starter.