BOSTON (AP) The Boston Red Sox acquired All-Star Drew Pomeranz from the San Diego Padres on Thursday night, adding a third left-hander to the rotation as they push to return to the playoffs after consecutive last-place finishes.
Boston sent righty Anderson Espinoza to San Diego. The 18-year-old righty was ranked the No. 15 prospect in the country by Baseball America.
''We think (Pomeranz) makes us better now,'' president of baseball operations Dave Dombrowski said in a conference call with reporters. ''We know there's a sacrifice for the future.''
Pomeranz, 27, who will make his Boston debut Wednesday, is 8-7 with a 2.47 ERA in 17 starts for San Diego this season. He pitched a scoreless inning in Tuesday night in the All-Star game.
''He's not an easy guy to deal,'' Padres general manager A.J. Preller said. ''Any time you have a left-handed starter who performs the way he has, resulting in an All-Star berth, you have to feel very good about the return that you're getting.
''I think it says a lot to Espinoza as far as what our guys thought about him. From that standpoint, we looked at it that it's something where we're getting a premium guy.''
Pomeranz joins fellow lefties David Price and Eduardo Rodriguez in a Boston rotation that includes Rick Porcello and AL ERA leader Steven Wright. Except for Wright, all have been inconsistent this season, and injuries to closer Craig Kimbrel and setup man Junichi Tazawa threatened to further strain the rotation.
''There are only a couple of pitchers we thought had a chance to be available that we thought would give us an upgrade on our pitching staff,'' Dombrowski said.
It's the fourth trade in a week for Dombrowski, who also made a big splash in the offseason by signing Price to a seven-year, $217 million free-agent contract. The Red Sox acquired third baseman Aaron Hill from Milwaukee, second baseman Michael Martinez from Cleveland and righty Brad Ziegler over the last seven days without giving up any major leaguers.
They have also managed to hang onto most of their top prospects. Espinoza was 5-8 with a 4.38 ERA in 17 starts for Single-A Greenville this season.
He was ranked as the No. 3 prospect in the Red Sox system and the No. 4 pitching prospect in the country, according to Baseball America.
''He's a youngster that we liked a great deal,'' Dombrowski said. ''He was a few years away from the major leagues. Not somebody that we wanted to give up.''
Preller, who traded Kimbrel to Boston over the offseason, has now traded two All-Stars in two weeks; he sent closer Fernando Rodney to Miami on June 30. Pomeranz is under Boston's control through 2018.
To make room for Pomeranz on Boston's 40-man roster, infielder Josh Rutledge was transferred to the 60-day disabled list. He has left knee tendinitis.
AP Sports Writer Bernie Wilson in San Diego contributed to this report.