BOSTON -- The rivalry has been back to its riveting best the last two weekends, and no lead ever feels safe.
The Yankees and Red Sox traded impressive comebacks in Friday night's series opener, but Boston prevailed with a 9-6 victory that had Fenway Park rocking in the late innings -- and with good reason.
With the win, the Red Sox opened up a five-game lead over the Yankees in the American League East. This, on the strength of a surge in which manager John Farrell's team has ripped off 13 wins in the last 15 games.
• Offense key to relentless Red Sox's surge
"It's just the tenacity of the group as a whole," said Farrell. "Once we turned into the month of August, the offense has turned it on. It's not any one guy. There's contributions up and down the lineup."

Mitch Moreland's pinch-hit two-run single to center against Tommy Kahnle put the Sox ahead for good in a game that swayed back and forth wildly. Moreland capped the damage in a four-run seventh that came just a half-inning after the Yankees had scored four to take a 6-3 lead.
"Three changeups, obviously," said Moreland. "First two, kind of pulled off them a little bit. Couple good pitches. Probably the first one was the best one I had to hit the whole at-bat. But on the third one, I just tried to tell myself to stay back and see it a little deeper and put a good swing on it, and I was able to do that and got it up the middle for a knock there."
Gary Sanchez's mammoth homer to left against Joe Kelly leading off the seventh tied the game as the Yanks erased a 3-0 deficit. The Bombers took their first lead of the night on a two-run single by Ronald Torreyes. However, in the recent rivalry matchups, momentum during a game has been a temporary thing.

Last weekend, the Yankees won the opener by roaring back from a 3-0 deficit in the eighth. The Red Sox took the rubber match with a thrilling comeback to take two out of three in the series.
To return the favor, the Yankees will have to win the next two days.
"It's a tough loss," Yankees manager Joe Girardi said. "Our guys fought really hard to get back in front with the lead and had really good at-bats from a lot of people. It's frustrating, but we'll be back."
• Aroldis gets animated mound visit from Girardi
Rafael Devers and Christian Vazquez served as catalysts for the Red Sox in this one. Devers smashed a two-run homer against Jordan Montgomery in the second. Vazquez went 3-for-3 with a homer and reached base four times.
"Yeah, it's a big win," said Vazquez. "Every win is big for us. We're trying to expand that lead for first place. We know we're playing good ball here, we're playing well."

The Yankees caught a break when Red Sox starter Thomas Pomeranz had to leave his scoreless outing in the top of the fourth inning with back spasms. That created a long night for Boston's bullpen, and New York capitalized with six runs to take a 6-3 lead into the bottom of the seventh.
• Pomeranz exits in 4th with back spasms
As it turns out, this one was just getting started.
MOMENTS THAT MATTERED
Benintendi's two-out knock: With two outs in the seventh, Andrew Benintendi made Moreland's go-ahead hit possible when he laced an RBI single against Kahnle to bring Boston within one. It was the continuation of a monster August for Benintendi, which has coincided with the Red Sox getting equally hot as a team. Benintendi's big hit came on a 1-1 changeup. For the month, the left fielder is hitting .392 with 14 runs, three doubles, five homers and 14 RBIs.

Judge strikes out: On a night when the Yankees went 1-for-11 with runners in scoring position and left 14 men on base, a pair of Aaron Judge at-bats loomed large. Judge grounded out to leave the bases loaded after a terrific battle with Joe Kelly in the sixth inning, then got another chance in the seventh after Torreyes' two-run single, a walk and a hit-by-pitch filled the bags again. Addison Reed struck out Judge swinging, marking the 35th consecutive game in which Judge has fanned, and Sanchez lined out softly as New York settled for a four-run frame. It was a big moment for Reed, who squandered a three-run lead in his first rivalry appearance a week ago.

"It was a big opportunity and A.R. handled it with poise facing a very talented hitter," said Red Sox center fielder Jackie Bradley Jr. "That was big. That was a big momentum shift for us."
"I'd rather have it turn out in a different way," Judge said. "I worked the count, fouled off some tough pitches and they just got the best of me that time."
QUOTABLE
"We have a lot of faith in one another. We feel like if one person doesn't get the job done, we feel like the next person will. And when you have that faith in each other, you put together some great things." -- Bradley, on Boston's surge
SOUND SMART WITH YOUR FRIENDS
Devers joined Hall of Famers Babe Ruth, Ted Williams and Ken Griffey Jr. as the only hitters since at least 1913 to homer in consecutive games against the Yankees before the age of 21.

It turned out the Red Sox had the right guy at the plate in Moreland for what proved to be Friday night's key at-bat. Since the start of the 2014 season, Moreland leads the Majors with a .459 batting average (minimum 40 plate appearances) as a pinch-hitter.
BENINTENDI GETS FIVE STARS
In the top of the fourth, Didi Gregorius stung a liner to left, but Benintendi got a terrific jump and made a sprawling catch to take a hit away. Statcast™ rated it as a five-star catch, the first of Benintendi's career. Benintendi had a Catch Probability of 14 percent and the Hit Probability for Gregorius was 71 percent. Benintendi needed to cover 41 feet of distance with an opportunity time of three seconds.

WHAT'S NEXT
Yankees:Carsten Sabathia will be activated from the disabled list on Saturday after lasting just three innings in his most recent start on Aug. 8 at Toronto due to right knee discomfort. Sabathia has had Boston's number this season, winning both of his starts while hurling 14 scoreless innings and permitting just seven hits. First pitch at Fenway Park is scheduled for 7:10 p.m. ET.
Red Sox: Ace Chris Sale gets the start in the middle game of this three-game rivalry series. The lefty has turned in three dominant performances against the Yankees this season, going 0-1 with a 1.19 ERA. Then again, that's in line with how Sale has fared in his entire career (4-2, 1.18 ERA in 13 appearances ) against New York.
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