The Red Sox had the best record in the majors after they beat the Twins in the series opener. But after losing 5-3 in Thursday night's finale, they dropped out of first place in the AL East for the first time this season.
"It's important that you kind of get that feeling about grinding things out (at) the end of a long road trip," Twins manager Ron Gardenhire said. "These guys really stayed focused."
Boston won the opening game of the series 6-5 in 11 innings on Monday night. Then Minnesota came back to finish the road trip at 5-5.
"To lose that first one, we could have very easily won that one, too," Minnesota starter Kevin Correia said. "So to come back and win three is huge."
The Twins were 4 1-2 games out of first place in the AL Central when they arrived in Boston. They left trailing by 2 1-2.
The Red Sox started the series with a 1 1-2 game lead over New York and Baltimore. They ended it percentage points behind the Yankees and tied with the Orioles for second.
"I don't think anybody is worried about the last seven games," Red Sox second baseman Dustin Pedroia said. "It is the big leagues and everybody is good."
Lackey was pitching very well until his wild throw to second base on a potential inning-ending double play gave the Twins another chance in the sixth and they responded with four unearned runs, including two on Arcia's homer, to take a 5-2 lead.
"I have to make that one play and we win the game," Lackey said. "One play ruined it all."
Correia (4-2) pitched 5 1/3 innings, his second shortest outing in seven starts this season. Then Brian Duensing got out of a sixth-inning jam and Gardenhire kept him in for the seventh. He finished with 1 2/3 hitless innings.
"I appreciate the confidence" Gardenhire showed, Duensing said. "These are the type of situations you want to be in as a reliever."
Lackey (1-3) pitched well until his error, then came back to pitch a perfect seventh before Koji Uehara took over in the eighth. Lackey allowed six hits and one walk and struck out eight. The Red Sox finished with 11 strikeouts, the 21st time in 35 games they've had at least 10.
Boston threatened with one out in the eighth when Daniel Nava walked and Will Middlebrooks reached first when shortstop Eduardo Escobar bobbled his grounder. It was the Twins' first error in 12 games. But Burton struck out Stephen Drew and Mike Carp.
Trailing 2-1, the Twins went ahead to stay in the sixth.
The inning began with a single by Joe Mauer. He took second on a one-out walk to Justin Morneau before Lackey flubbed a chance to get out of trouble. Trevor Plouffe grounded the ball back to the mound, but Lackey threw wildly past Pedroia into center field. Mauer scored on the play, tying the game.
"You're looking for breaks in the game," Gardenhire said, "and that was a break for us."
Ryan Doumit's sacrifice fly gave Minnesota the lead before Arcia hit the next pitch into the right field seats for his third homer of the season.
"The errant throw opened the door for them," Boston manager John Farrell said. "In the sixth inning (Lackey) was his own worst enemy. Other than that, I thought he pitched really well."
The Red Sox had scored the first run of the game in the third on a double by Shane Victorino and an RBI single by Pedroia. They made it 2-0 in the fourth when Nava singled, took second on a groundout and scored on Drew's single.
The Twins scored a run in the fifth when Arcia tripled and scored on a double by Aaron Hicks.
After falling behind 5-2, Boston scored in the sixth on a leadoff double by Mike Napoli and a run-scoring single by Nava. Middlebrooks then grounded into a forceout. Duensing replaced Correia and retired the next two batters.
That was one of many wasted opportunities for Boston, which left exactly one runner on base in each of the first seven innings, two in the eighth and one in the ninth.
Twins SS Pedro Florimon was listed as day to day after leaving the game in the bottom of the seventh with a tight right hamstring. ... The Red Sox transferred closer Joel Hanrahan from the 15- to the 60-day disabled list. He is scheduled to see orthopedist James Andrews on Friday, an examination that could determine if he needs surgery after suffering a strained right forearm. ... Boston opens a three-game series at home with the Toronto Blue Jays on Friday night with Jon Lester (4-0) pitching for the Red Sox against Ramon Ortiz (0-0). ... Minnesota starts a nine-game homestand Friday with Mike Pelfrey (3-3) pitching for the Twins against Jason Hammel (5-1) of the Orioles.