Perhaps one day, some of the 31,422 fans at Fenway Park on Monday night will proudly lay claim to having attended Roman Anthony’s major league debut. But few who do so will be able to recall the details of a misty, dizzying slog.
Though he went 0 for 4, Anthony demonstrated some of his offensive trademarks, including a patient approach and an ability to hit the ball hard. He contributed a walk as well as an RBI groundout that contributed to a game-tying ninth-inning rally — one of three times the Sox erased a Rays lead to tie the game.
But in his first game action in right field since May 2, Anthony also had a rookie misplay, committing a run-scoring, two-base error on a single, which played a role in the Red Sox’ 10-8 loss in 11 innings to the Rays. The Sox lead all of baseball with eight extra-inning losses, a pattern that has contributed to their sub-.500 (32-36) standing.
Nonetheless, the top takeaway from Monday’s contest was the arrival of the top prospect in baseball.
“It was awesome,” reflected Anthony. “It was nice to finally just take the field and forget about all the outside noise. … Unfortunately, we couldn’t get a win.”
Responsibility for the loss fell chiefly on a lineup that couldn’t take advantage of repeated opportunities (4 for 23 with runners in scoring position), a taxed bullpen that got throttled for six runs in four innings, and defensive misplays that amplified Rays rallies.
Sox starter Brayan Bello was sharp early, as he and Rays counterpart Shane Baz traded zeroes through three innings. The Rays broke through with a run-scoring infield single in the fourth and two more runs in the fifth — an outburst that arose from Bello hitting No. 9 hitter Danny Jansen and two outfield misplays of two-out Rays hits.
Jarren Duran fumbled a Brandon Lowe single to left, allowing Jansen to score from second without a throw. Yandy Díaz followed with a single to right that skipped under Anthony’s glove and to the fence for a run-scoring two-base error.
“Just can’t happen,” grimaced Anthony. “I’ve dealt with that skip a million times in my career. It’s tough when you lose a game like that. You feel like that’s the reason why we lost, little things like that. So, it’s tough, but just going to learn from it and be better.”
Down 3-0, the Sox punched back. They scored a run in the fifth, then two more in the sixth when pinch hitter Romy González flipped a two-out, two-run double down the right-field line against lefthanded reliever Garrett Cleavinger to tie the game, 3-3.

But Bello and the Sox immediately gave back the advantage. Bello, who became the first Sox pitcher other than Garrett Crochet to log at least six innings in back-to-back outings since April 27-May 2, returned to the mound for the seventh, but issued a leadoff walk and, after a pop-up, concluded his night after 6 innings.
Reliever Brennan Bernardino immediately allowed an RBI double to Josh Lowe that put the Rays ahead, 4-3, and closed the book on another strange outing from Bello.
The starter allowed four runs (three earned) on seven hits while walking one and striking out four. Bello’s mix was once again atypical, as he threw more sweepers than any other pitch, and used his changeup sparingly. He avoided few bats but limited the Rays to weak contact.
“I felt very good today,” Bello said through a translator. “I feel happy I’m improving and that I’m going in the right direction.”
However, a bullpen meltdown followed Bello’s departure. After Lowe’s RBI double, Bernardino contributed an errant pickoff throw and, and an intentional walk, uncorked a wild pitch to score another run, then gave up a two-out single as the Rays claimed a 6-3 lead.
Disgusted by the performance, Bernardino fired his glove and hat into the dugout as he came off the field — the cumulative frustration of a month in which the oft-used reliever (31 appearances in 68 games) has allowed at least one run in all four of his outings.
“He’s been used a lot,” said manager Alex Cora. “The command may suffer. The stuff, too. But this is a guy, he’s been good for us throughout the season and a guy we believe in.”
Still, the game took several turns. The Sox tallied a pair of runs in the seventh, and then after a Rays insurance run in the top of the ninth, fought back to tie the game in the bottom of the inning.
With men on second and third and one out, Anthony smoked a grounder up the middle against Rays closer Pete Fairbanks to score one run, and Kristian Campbell followed by chopping an infield single to make it 7-7 and send the contest to extras.
After both teams took advantage of the automatic runner to exchange runs in the 10th, Sox reliever Zack Kelly (1-3) issued a bases-loaded walk and run-scoring infield single in the 11th as the Rays took a 10-8 lead.
Middleborough native Ian Seymour (a St. John’s Shrewsbury alum) — aided by a generous called third strike against González that resulted in an argument and ejection for Cora — then delivered a scoreless 11th inning to earn a win in his big league debut.
The Sox were left with a familiar lament.
“Just got to get better,” said Cora.
They hope Anthony will be a contributor who helps them do just that.
Alex Speier can be reached at alex.speier@globe.com. Follow him @alexspeier.