BOSTON — The naked aggression shown on the bases by the Blue Jays at Fenway Park has been typical of Red Sox opponents this season.

Lourdes Gurriel Jr. taking off for home plate on a straight steal attempt was as brash as it has become common. Toronto’s second baseman slid in head-first as Chris Sale whipped a pitch to the backstop, one of the lowlights in Tuesday’s 7-5 defeat.

Gurriel is part of a 9-for-10 start by opposing [...]

BOSTON — The naked aggression shown on the bases by the Blue Jays at Fenway Park has been typical of Red Sox opponents this season.

Lourdes Gurriel Jr. taking off for home plate on a straight steal attempt was as brash as it has become common. Toronto’s second baseman slid in head-first as Chris Sale whipped a pitch to the backstop, one of the lowlights in Tuesday’s 7-5 defeat.

Gurriel is part of a 9-for-10 start by opposing baserunners against Boston in the early going. The Red Sox threw out 31.9 percent of opposing runners last season, allowing just 64 steals through 162 games. Blake Swihart has the lone recorded out to his name in four chances while catching partner Christian Vazquez is 0-for-6.

“That’s something that the last two World Series teams did and took advantage,” Red Sox manager Alex Cora said. “Just like football or the NBA, I guess — it’s a copycat league.”

Boston swiped 125 bags to rank third in the American League last season, adding the running game to a punishing offensive attack at the plate. The Astros ranked fourth in the A.L. with 98 stolen bases on the way to their 2017 title, and Cora was the bench coach for that club under manager A.J. Hinch.

“Teams, when you have the lead, can do a lot offensively,” Cora said. “And we did it last year as an offense. When you get the lead, you start pushing the envelope.”

Vazquez was 13-for-35 throwing out opposing runners last season while Swihart was 5-for-19. Sandy Leon was just 9-for-35, seemingly the only weakness in his otherwise superlative defensive ability. The pitching staff also shoulders some of the blame — Sale was in the windup with Gurriel at third base and his attempted adjustment on what was supposed to be a slider went awry.

“I just kind of pushed it the other way,” Sale said of the pitch to left-handed hitter Billy McKinney, one that zipped through the vacant right-handed batter’s box. “That’s part of it. I’ve got to be prepared for that.”

Weather woes

Mitch Moreland might well have had a pair of home runs if not for the wretched conditions at Tuesday’s home opener.

Moreland pulled a drive into the visiting bullpen in the first inning and sent another shot to deep center leading off the fourth that was run down by Randal Grichuk. The 41-degree chill and seasonal cold wind blowing in off the Charles River from left field does hitters no favors this time of year in the Back Bay.

“He runs into stretches that he becomes pull-happy and he’s off-balance at the plate,” Cora said. “But when he’s right, he’s able to drive the ball to left center. When they hand him something in the middle of the plate, he can drive it out of the ballpark.”

Moreland’s 1.036 OPS through 12 games topped the Red Sox. Only Swihart was within 100 points, checking in at 1.009, thanks mostly to a double and a home run in 19 plate appearances. Moreland reported healthy and ready for spring training in what is a contract year for the first baseman.

Power outage

Andrew Benintendi entered Thursday with just three extra-base hits in 46 plate appearances, one of several Boston players off to a bit of a slow start in the power department.

Benintendi tripled in a 6-3 win at Oakland on April 3 and stroked doubles in back-to-back games at Arizona on Friday and Saturday. The left fielder hit just two of his 16 home runs after July 7 last season and is awaiting his first round-tripper in 2019.

“As far as his swing, it’s very simple with him,” Cora said. “If you want to talk about pure hitters, he is. Just a matter of not expanding the zone and staying off the edges.”

Benintendi’s walk rate was a solid 10.6 percent in his first full season in 2017 and rose a tick to 10.7 percent in 2018. He’s down to 7.7 percent in the early stages of 2019 and striking out 23.1 percent of the time.

“I think it’s pitch selection,” Cora said. “He’s been swinging at some pitches on the edges of the strike zone. When you do that most of the time, there’s no solid contact.”