Coming into the weekend the Arizona Diamondbacks ranked as arguably the best team in baseball since the All-Star break, while the Boston Red Sox have been among the worst. Sitting 3.5 games below the playoff cutline entering Friday, the Red Sox really needed to flip that trend and avoid losing any more ground.

Instead they got run out of their own ballpark.

The Diamondbacks completed a demoralizing three-game sweep at Fenway Park on Sunday, scoring seven unanswered runs to rally past the Red Sox 7-5.

Eugenio Suarez delivered the dagger with his go-ahead three-run home run in the top of the sixth, and the Red Sox have gone 2-7 with two sweeps in their last three home series dating back to the start of August. They now sit 4.5 games out of the playoffs heading into the new week.

After struggling offensively through the first two games of the series, Boston got off on the right track Sunday thanks to two early home runs. Triston Casas crushed a solo homer 420 feet into the right field bleachers in the bottom of the first, and Rafael Devers smoked a three-run shot to dead center in the fourth to make it 4-0 Red Sox.

It was Devers’ 28th home run of the season and the 200th of his career. Devers is now the 11th player in franchise history to hit 200 home runs as a member of the Red Sox, and at 27 years and 306 days old he’s also the youngest to reach the mark, surpassing the previous record held by Jim Rice (28 years, 62 days).

“There have been so many great baseball players coming through this organization, this is one of the best organizations with the most history in baseball and for me to be in that conversation is great,” Devers said via translator Carlos Villoria Benítez. “But I know that I still have a lot more to give to this organization, I don’t want to stop at 200, 250, I’m still young and I want to keep going and improving those numbers.”

Boston could have tacked on more but let the opportunity slip away. Masataka Yoshida followed Devers’ big hit with a double down the right field line, but he got greedy and was thrown out at third by a mile trying to leg out a triple. That misstep cost the Red Sox a run when Connor Wong immediately hit a double of his own, which would have scored Yoshida had he held up safely at second.

The Red Sox could have used the cushion given what happened next.

Tanner Houck had been cruising along for most of his outing, benefiting from three double plays in the first four innings. He could have badly used a fourth in the top of the fifth, but after allowing a walk, a single and another walk to load the bases with no outs he wasn’t able to escape unscathed.

All three runners came around to score on a Geraldo Perdomo groundout, a Corbin Carroll sacrifice fly and a Jake McCarthy RBI single. Tyler O’Neill’s decision to throw home on the sacrifice fly rather than to third likely also cost Boston a run given that Luis Guillorme probably wouldn’t have scored on McCarthy’s single if he had been held at second. Instead he advanced to third and scored to cut the deficit to 4-3.

Boston squandered a prime opportunity to regain the momentum in the fifth when Jarren Duran and Wilyer Abreu led off with back-to-back walks before Casas flied out and Devers grounded into a double play. Then Houck lost the plot completely, allowing a single, his fourth walk and then a back-breaking three-run home run to Suarez.

The Red Sox won’t be sad to see Suarez leave town after this weekend. In three games the Diamondbacks outfielder has gone 8 for 13 (.615) with two home runs, a double and 10 RBI. He finished 4 for 4 with the three-run homer on Sunday.

“He was a monster the whole weekend,” Red Sox manager Alex Cora said.

Houck finished with six runs allowed on seven hits, four walks and two strikeouts over six innings. His four walks tied a season-high, and what was looking like another quality start quickly snowballed into one of his worst outings of the year.

“Early on it felt like I was pounding the zone, going right after guys, a little bit later on I was off the zone, out of the zone too much with everything,” Houck said. “That being said, I beat myself today with the walks, so that’s all you can really say.”

“He was erratic today,” Cora said.

The late meltdown was particularly ill-timed given that Arizona starter Merrill Kelly also had a tough outing by his standards. Kelly went six innings as well but allowed four runs on seven hits and three walks with five strikeouts.

Perdomo finished the scoring for Arizona by curling a solo home run around Pesky’s Pole in the top of the ninth off Lucas Sims, and O’Neill provided the last gasp for Boston by going opposite field for a Pesky’s Pole shot of his own.

But that was all Boston could manage offensively, and after falling behind in the sixth the Red Sox managed only two baserunners the rest of the way, striking out seven times in the last four innings.

Boston didn’t help its own cause by grounding into three double plays of its own. Two of those came off the bat of Duran, who had grounded into only two double plays in 126 games all season entering Sunday.

The only good news after Sunday’s sweep is the most difficult stretch of Boston’s season is finally over. Since July 12 the Red Sox have played 25 of 37 games against teams currently in playoff position, going 16-21 over that span, but now they’ll play 14 straight games against teams currently out of the playoffs.

First up will be the Toronto Blue Jays, who the Red Sox play five times in the next four days starting with the continuation of the suspended game from June 26 as part of Monday’s doubleheader.

“We’ve turned the page, there’s always a light at the end of the tunnel and baseball is a really funny game,” Casas said. “It has no remorse, it doesn’t favor the hardest working or the nicest people, it’s just who comes out to play that day and we’ve got to come out and do that tomorrow.”

Hendriks update

Right-hander Liam Hendriks threw his third of what is expected to be six or seven minor league rehab outings on Sunday in Portland, going 0.2 innings while allowing one run on one hit with two strikeouts. Hendriks threw 19 pitches, 13 for strikes, before handing the ball off to Jacob Webb to finish the top of the sixth.