It's a new era in Boston, but a lot still remains the same.

After completing arguably the biggest waiver-wire trade in the history of Major League Baseball with the Los Angeles Dodgers earlier Saturday, the Red Sox blew a six-run lead for the second time in three days and lost to the Kansas City Royals, 10-9, in 12 innings to conclude a wild day in Beantown.

In the top of the 12th, Jeff Francoeur worked a two-out walk against Junichi Tazawa (0-1) before Eric Hosmer banged a double off the Green Monster in left field. Tony Abreu then drove home Francoeur when he lined a single the other way into left field.

"When you battle back from being down six runs, that's a good win," Royals manager Ned Yost said. "I don't know how you sum it up, but I never felt like we were ever out of that game."

Francisley Bueno (1-0) picked up the win after tossing 1 2/3 scoreless innings, while Greg Holland fired a 1-2-3 12th to nail down his seventh save of the year.

The Red Sox, who racked up 20 hits, threatened in the bottom of the 10th inning as they had runners on the corners with one out, but Pedro Ciriaco was thrown out at home when Jacoby Ellsbury bounced one to first base.

Boston squandered a six-run cushion to the LA Angels of Anaheim in a 14-13, 10-inning loss on Thursday.

As things began to unravel in Boston for a second consecutive season, the Red Sox decided to start fresh and shed away approximately $270 million in the blockbuster deal earlier in the day.

Boston sent first baseman Adrian Gonzalez, outfielder Carl Crawford, right- hander Josh Beckett and infielder Nick Punto to the Los Angeles Dodgers in exchange for first baseman James Loney and two prospects -- pitcher Allen Webster and infielder Ivan De Jesus -- along with two players to be named later.

Gonzalez, acquired by Boston in a trade from the San Diego Padres following the 2010 season, is set to earn $133 million over the next six years of his contract, a deal struck by former Red Sox GM Theo Epstein that expires following the 2018 season. Crawford, another Epstein acquisition who is signed through 2017, is due $108.5 million over the next five years.

Beckett still has $31.5 million remaining through the end of his deal in 2014 and Punto will make $1.5 million in 2013, the final season of a two-year package.

"We are absolutely committed to building the best team in 2013 and beyond, and we will do that in the most disciplined way possible," Red Sox general manager Ben Cherington said at a Saturday press conference. "We have a core of players here, still, that will be a part of our next great team."

Mauro Gomez, Gonzalez's replacement at first base, went 4-for-6 with his first Major League homer and three RBI.

The Red Sox led 9-3 after plating nine unanswered runs in between the second and fourth innings, but Kansas City tied it after pushing across six in the seventh.

Alex Gordon hit a two-run single before Billy Butler plated a run with a ground-rule double to right. Salvador Perez then singled to right before Mike Moustakas' triple brought home a pair to knot the contest at 9-9.

Earlier, the Royals struck for three runs in the opening frame when Gordon smacked a two-run double to left field and Butler followed with a run- scoring single.

Gomez belted a homer to left field in the second and three batters later, Mike Aviles cracked a three-run blast just over the Green Monster in left field, which gave Boston a 4-3 lead.

With the bases loaded in the third, Gomez's dribbler down the third-base line plated Dustin Pedroia, who led off the inning with a ground-rule double. Ellsbury, who walked following Pedroia's double, also scored on the play when Jeremy Guthrie's throw home to nab Pedroia got away from the catcher Perez. Jarrod Saltalamacchia followed with a sacrifice fly to center field for a 7-3 Boston margin.

Cody Ross and Gomez hit back-to-back RBI singles to left field in the fourth to make it 9-3.

Game Notes

Kansas City was 8-for-13 with runners in scoring position, while Boston finished 5-for-11 ... Guthrie allowed seven runs -- six earned -- on seven hits and two walks in 2 2/3 innings ... Boston starter Aaron Cook surrendered three runs on seven hits and a walk over six frames ... The Red Sox fell to 2-8 in extra-inning games ... Moustakas' two-run triple in the seventh snapped an 0-for-18 drought.