The Red Sox finally announced their full rotation for the team's weekend series against the Houston Astros at Fenway Park on Friday morning. Then they went around and changed it again Friday afternoon, with newcomer Dustin May no longer set to make his Boston debut on Sunday. 

The 27-year-old right-hander, who was acquired from the L.A. Dodgers ahead of Thursday's MLB trade deadline, was set to debut for the Red Sox in Sunday's series finale against Houston. He's still set to join the team Saturday, but Sunday will no longer be a May Day in Boston.

Instead, veteran Lucas Giolito will now take the mound Sunday afternoon. Boston manager Alex Cora said May wasn't pushed back for a health issue, but because Giolito was going to have six or seven days off following his July 29 start. The veteran wasn't a fan of such a long break.

"A lot of days between starts and Gio didn't like that," said Cora, joking he was trying to give the veteran a break with Sunday's game starting at 11:35 a.m. 

One name you won't see listed among Boston's starters is ace Garrett Crochet, who is being given a few extra days of rest with 141.1 innings pitched already under his belt this season.

Crochet was set to start Friday night's series opener, but will instead pitch Tuesday in the middle game of a three-game set with the Royals in Kansas City. Brayan Bello is set to start the series opener on Monday, and May will make his debut Wednesday in the series finale.

The Red Sox hadn't announced Crochet's replacement for Friday night until late Friday morning, with recent Triple-A call-up Cooper Criswell set to toe the rubber at Fenway Park to start the three-game series.

Friday: Hunter Brown (9-5, 2.54 ERA) vs. Cooper Criswell (1-0, 5.06 ERA)

Criswell has made six relief appearances for Boston this season, but hasn't pitched in the big leagues since 1.2 innings of scoreless relief back on July 2. He made 13 starts (and 14 appearances overall) for Worcester and went 4-2 with a 3.32 ERA at the Triple-A level.

He was 6-5 with a 4.08 ERA and 1.349 WHIP across 26 appearances (including 18 starts) for Boston last season. For his career, Criswell is 5-4 with a 3.71 ERA and 1.442 WHIP over 20 starts over his four MLB seasons.

The Astros are starting Brown, who was excellent to start the season but struggled through the month of July. The 26-year-old righty went 0-2 with a 5.54 ERA over his five July starts, when he allowed 27 hits and issued 10 walks over 26 innings. He allowed only one run over five innings his last time out, but took the loss in a 5-1 defeat at the hands of the homeless Athletics.

Saturday: Colton Gordon (4-3, 4.74 ERA) vs. Walker Buehler (6-6, 5.72 ERA)

Buehler went only 4.2 innings his last time out, when he issued five walks and allowed three runs in a win over the L.A. Dodgers. But he was much better in July than other months this season, when he allowed just nine earned runs over his 22.2 innings of work. It lowered his ERA from 6.45 to start the month to the 5.72 ERA he brings into Saturday's start.

Gordon is in his first season in the big leagues, and is looking to put a tough July behind him. The lefty gave up four runs off two homers and six hits his last time out in a loss to the Athletics. Gordon had a 6.14 ERA last month, when he allowed five homers and 16 runs over 22 innings.

Saturday afternoon will be Gordon's first career start against the Red Sox.

Sunday: Framber Valdez (11-4, 2.62 ERA) vs. Lucas Giolito (7-2, 3.80 ERA) 

May's debut has been put on hold after he was initially announced as Sunday's starter. Giolito will toe the rubber instead, and will look to build off a solid win against the Twins last time out when he allowed one run over six innings. It was a nice bounce-back effort for the veteran, who had allowed nine earned runs over 9.1 innings in his previous two starts against the Cubs and the Philies.

He'll be opposed by Valdez, who is having another excellent season for the Astros. He's been great against the Red Sox over his career, bringing a 3-1 record and 1.96 ERA in five games against Boston into Sunday's finale.

Programing note: Sunday's game is a few hours earlier than usual, with first pitch scheduled for 11:35 a.m. because it's airing exclusively on Roku.