TAMPA (Interstat) — Marcelo Mayer’s third-inning home run accounted for all of Boston’s offense Monday night, but Yandy Díaz answered with a solo shot of his own and Jonathan Aranda delivered the go-ahead RBI single as the Tampa Bay Rays defeated the Boston Red Sox 3-1 at George Steinbrenner Field.

Boston dropped to 27-37 with its second consecutive loss, while Tampa Bay improved to 38-25, winning for the third time in four games. The announced attendance was 14,579, and the game lasted 2 hours, 45 minutes.

Rays right-hander Casey Legumina earned the win, improving to 2-1. He allowed one run on three hits over five innings, striking out eight and walking one. Bryan Baker pitched the ninth for his 17th save. Red Sox lefty Connelly Early took the loss, falling to 5-4, after yielding two earned runs on five hits in 4-2/3 innings with six strikeouts and two walks.

The Rays struck first in the bottom of the first when Díaz launched his 12th home run of the season to left field. The solo blast came on a 2-2 pitch and gave Tampa Bay an early lead. Boston answered in the top of the third when Mayer, the rookie shortstop, drove a 1-0 fastball to right-center for his third homer of the year, tying the game at 1-1.

The game remained deadlocked until the bottom of the fifth. With one out, Austin Slater singled to third base and promptly stole second, his second steal of the season. After Ryan Vilade flied out, Aranda lined a single to left field, scoring Slater and putting the Rays ahead for good.

Tampa Bay added an insurance run in the eighth. Taylor Walls led off with a walk, advanced to third on a groundout by Nick Fortes and scored on a sacrifice fly to center by Díaz, giving the Rays a 3-1 advantage.

Boston’s offense managed only four hits and never mounted a serious threat after Mayer’s homer. The Red Sox had a chance in the seventh when Willson Contreras was hit by a pitch and Mickey Gasper singled, putting runners at first and second with one out, but Rays reliever Tyron Guerrero struck out Caleb Durbin on a called third strike after a challenge overturned the original call, and Isiah Kiner-Falefa grounded out to end the inning.

Guerrero pitched 1-1/3 innings of one-hit relief with two strikeouts, keeping Boston scoreless. Alec Gamboa contributed 2/3 of an inning with one strikeout. Greg Weissert worked 1/3 of an inning, allowing one hit but no runs.

For Boston, Early battled through five innings, working out of a bases-loaded jam in the second after a hit-by-pitch and a bunt single. He struck out Nick Fortes and got Austin Slater to line out to end that frame. The lefty also induced a double play in the third after issuing consecutive walks.

Gasper and Wilyer Abreu each had one hit for the Red Sox. Ceddanne Rafaela singled in the sixth but was caught stealing. Contreras went 0-for-3 with a hit-by-pitch. Durbin, Kiner-Falefa, Andruw Monasterio and Carlos Narváez combined to go 0-for-9.

Díaz finished 1-for-3 with two RBIs and a walk. Aranda went 2-for-4 with the RBI. Slater scored the go-ahead run. Rays pitchers combined to strike out 14 Boston hitters, with Legumina accounting for eight of them.

The game marked the first meeting between the teams since May 10, when Tampa Bay won 4-1 in Boston. The Rays have now taken two of three in the season series.

The most critical sequence occurred in the bottom of the fifth, when Slater’s single and stolen base set up Aranda’s go-ahead hit. That inning broke a 1-1 tie and forced Boston to play from behind for the remainder of the night. The Red Sox could not recover, stranding four runners over the final four innings.

Boston’s bullpen held Tampa Bay to one earned run over 3-1/3 innings, but the offense could not support the effort. The Red Sox have now lost 10 of their last 15 games, while the Rays have won eight of their last 12.

The two teams conclude the brief two-game series Tuesday before Boston returns home to face Texas and Tampa Bay travels to Los Angeles.

Interstat’s game simulator projected a final score of Boston 4, Tampa Bay 3, while its ELO system gave the Rays a 52.30 percent probability of winning. Boston was installed as a pregame favorite with a spread of minus-1.5. The total of four runs went over the over-under line of 7.5.