BOSTON — The Orioles are running out of time to kick-start their offense.

With 18 games left on their regular-season schedule, Monday’s series opener against the Red Sox offered plenty of opportunities to put up some crooked numbers on the Fenway Park scoreboard. Instead, they stranded 11 base runners and their bullpen crumbled late as they fell to their division rivals, 12-3, for their third straight loss.

Anthony Santander did his part, becoming the eighth player in Orioles history and first since Mark Trumbo in 2016 to hit 40 home runs in a season with a solo shot in the seventh inning. He drove in all three of the team’s runs to improve his team-leading RBI total to 94, but Baltimore otherwise squandered scoring chances in each of the first four frames.

The Orioles loaded the bases in the first and fourth innings and walked away with only one run each time courtesy of Santander. He scored Gunnar Henderson on a hard-hit single in the first before later bringing Colton Cowser home on an RBI walk. Otherwise, the Orioles went 1-for-10 with runners in scoring position to stay true to what has become an all-to-familiar theme over the past three months.

Rookie starter Cade Povich, coming off the best start of his young career with 7 1/3 scoreless innings against the Chicago White Sox, got an early hook from manager Brandon Hyde after allowing a lot of hard contact, including back-to-back home runs by Rob Refsnyder and Tyler O’Neill in the third that helped Boston jump out to a 4-1 lead.

He lasted two outs into the fifth before giving way to Burch Smith, who got out of the inning with some help from his defense. Cowser played a fly ball off the Green Monster perfectly and fired a 95.1 mph throw home that Adley Rutschman gathered before making a diving tag to nab Refsnyder trying to score from first. The play was part of a defensive clinic put on by the Orioles’ outfield with Cedric Mullins making a diving catch in center field in the third.But Smith unraveled in the sixth, loading the bases before Ceddanne Rafaela extended the Red Sox’s lead with a two-run single. Gregory Soto then came in to get out of the jam and Refsnyder struck again with a two-run single that made it 8-2. All four runs were charged to Smith, who has allowed 15 earned runs in his last 14 2/3 innings (9.20 ERA) dating to Aug. 6.

Craig Kimbrel’s equally unimpressive ongoing stretch continued as well. The demoted closer struck out the first two batters he faced in the seventh before giving up a single, stolen base, walk and two-run double by Rafaela. Since recording his latest save on July 7, Kimbrel has an 8.83 ERA over 18 appearances with three losses and two blown saves.

He was replaced by Cole Irvin, who became the second pitcher of the night to allow consecutive home runs to Refsnyder and O’Neill. Refsnyder came to the plate in the eighth a triple short of the cycle and had to settle for a multi-homer game, driving in his fifth RBI by poking one just inside of Pesky’s Pole in right field. O’Neill then capped off the evening with another Green Monster-clearing blast.

Baltimore (82-63) will send Albert Suárez to the mound Tuesday against Boston starter Kutter Crawford as the club looks to even the series.