BOSTON -- An electric atmosphere at sold-out Fenway Park made April feel like October, and the sea of blue shirts in the stands made it clear how many Cubs fans made the trek to Boston for this much-anticipated weekend series.
But the Red Sox stood their ground on their home turf, utilizing a big burst of offense in the bottom of the first and a strong late-inning effort by the bullpen en route to Friday night's 5-4 victory over the defending World Series champions.
When Craig Kimbrel ended it by striking out Addison Russell on 99.1-mph heat, the Fenway crowd erupted and catcher Christian Vazquez pumped his fist in triumph.

Boston's big first erased the early momentum generated by Kristopher Bryant. Last year's National League Most Valuable Player Award winner introduced himself to the Fenway crowd by unloading for a titanic solo shot over the Green Monster to make it 1-0 in the top of the first. Statcast™ gave it a projected distance of 449 feet, easily the longest homer at Fenway so far this season.

Throughout the night, even the spectators got competitive, as "Let's Go, Red Sox" chants were routinely countered by "Let's Go, Cubs."
"It was like a World Series game," said Vazquez. "They have a great team and great hitters, good players, and we do, too. Hope to see them in the World Series."
Fortunately for the rabid fans of both teams, there are still two more games this weekend.
Friday was definitely a tone-setter, as the two historic franchises played before a packed house of 37,054. The Cubs, with the collective return of Jonathan Lester, John Lackey, Koji Uehara and Theo Epstein, were the story coming in. The Red Sox, however, quickly stole some thunder by scoring five runs off losing pitcher Jacob Arrieta in the first. Andrew Benintendi's solo shot to right got that rally started for a team that has slumped offensively of late.

"It's definitely nice facing Arrieta to get out in front early, so five runs in the first is big," said Benintendi.
• Bullpen cop cheers Benintendi homer
Thomas Pomeranz gave the Red Sox six solid innings for the win, scattering six hits and two runs while walking two and striking out seven. The bullpen took it from there, with Joe Kelly, Fernando Abad and closer Kimbrel (eighth save) all recording big outs.
"It was a great atmosphere tonight," said Red Sox manager John Farrell. "The build-up to this weekend speaks for itself. Given the way that game went, they're chipping away, getting back into this ballgame, two strikeouts, he's facing the heart of that order, which is explosive, yeah, it's a great atmosphere for being in late April. Craig was outstanding."
For Arrieta, this start was nothing like his last outing at Fenway, when he had a no-hitter for 7 2/3 innings. Considering he threw 42 pitches in the first on Friday, Arrieta did well to last 4 1/3. Arrieta didn't allow a run for the remainder of his outing, which was his shortest since Aug. 28, 2014.
• Arrieta's 42-pitch first sets tone
"I know our guys are excited about playing here," Cubs manager Joe Maddon said. "Whatever excitement there was, it came back to normal levels rather quickly. I thought we played well. We just gave up too many runs too early."
MOMENTS THAT MATTERED
That five-run first: There was no better example of how quickly baseball can change than the bottom of the first inning. In Thursday's 3-0 loss to the Yankees, Boston's lineup saw just 97 pitches the entire game. In this one, they forced Arrieta to throw 42 in the first. Benintendi's homer to right, which had an exit velocity of 95.5-mph and a hit probability of just 25 percent, got the party started after barely clearing the wall.
Hanley Ramirez added a squibber of an RBI single to right that had an exit velocity of 67.5-mph and a hit probability of 12 percent. Jackie Bradley Jr's seeing-eye RBI single had a hit probability of 36 percent.

"They strung some hits together and came out ready to play in the first," Arrieta said. "From that point on, I knew my job was to get as deep in the game as I could."
It was a much-needed inning for the Red Sox, who came into the game tied for 12th in the American League in runs.
"Guys had some rhythm," said Red Sox second baseman Dustin Pedroia. "We found some holes, had some good at-bats in a row. So it was nice."
Cubs rally falls short: With Pomeranz out of the game, the Cubs looked primed to battle back against Boston's setup crew in the seventh. Almora led off with a walk against Robbie Scott. With two outs, Anthony Rizzo smashed Joe Kelly's 101.96-mph fastball to right for a single. That offering by Kelly was tied with Albertin Chapman for the second-fastest pitch in the Majors this season. Almora scored on a wild pitch by Kelly. Benjamin Zobrist made it a 5-4 game with an RBI single to center off a 98.8-mph heater by Kelly.
But Kelly made the pitch he had to, getting Addison Russell on a flyout to right to end the frame. It was Abad who snuffed out a rally in the eighth, striking out Kyle Schwarber with the potential tying and go-ahead runs on base.

The Cubs had chances, but stranded 10 and went 1-for-11 with runners in scoring position. That also was a problem Wednesday in a loss to the Pirates.
"Double-digit left on base stuff -- we've got to start moving runners across the plate," Maddon said. "We have them out there, we have the right guys coming up. We're not doing that with any consistency."
QUOTABLE
"It felt good. It was probably one of my favorite home runs, considering my family is from this area and my dad [was drafted by the Red Sox] and all that. It felt really good." -- Bryant, on his home run over the Green Monster

"It doesn't matter. Just add six-hole to the list. I rake in that spot, too." -- Pedroia, who had two hits and a walk while batting sixth for the first time in his career
SOUND SMART WITH YOUR FRIENDS
Bryant's blast in the first was the fifth longest at Fenway in the Statcast™ Era, which started in 2015. It also had the fifth-best projected distance of Bryant's 68 career homers. He's the first NL player to homer at Fenway in his first career at-bat there since Mike Olt did so July 2, 2014, also with the Cubs.
The sliding catch by Mookie Betts that robbed Ben Zobrist of a hit to end the top of the first was a 3-star play that had a catch probability of 58 percent, according to Statcast™.
DEMPSTER, LESTER EMERGE EARLY
Wearing a home Red Sox jersey with his familiar No. 46 on the back, current Cubs executive Ryan Dempster threw out the ceremonial first pitch before Friday's game. Dempster was part of Boston's World Series-winning team of 2013. Another member of that team, Lester, came out for the exchange of lineup cards. It was Lester's first trip back to Fenway since he was traded on July 31, 2014. During the game, the scoreboard panned on Uehara, as well as Lackey and Lester, drawing a favorable reaction from the Fenway faithful.

WHAT'S NEXT
Cubs: Lackey returns to Fenway Park for the first time since 2014. The right-hander, who pitched for the Red Sox from 2010-14, will start Saturday in the second game of this Interleague series. He's 31-23 in 67 starts at Fenway with a 4.45 ERA. First pitch is scheduled for 3:05 p.m. CT.
Red Sox: Knuckleballer Steven Wright will try to emerge from an early-season slump when he takes the mound for Saturday's 4:05 p.m. ET game against the Cubs. After giving up 12 home runs last season, Wright has already given up seven this year.
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