NEW YORK (AP) -- The Philadelphia Phillies bolstered their beleaguered rotation.
The 36-year-old is 6-5 with a 4.01 ERA, winning his last three starts. He became expendable when the Mets acquired right-hander Marcus Stroman from Toronto on Sunday night for a pair of pitching prospects.
''Jason Vargas is battle-tested and has been relatively effective for the better part of a decade now,'' Phillies general manager Matt Klentak said. ''He gives his team a chance to win the game every time he takes the ball. I like the fact it's a different look. He's a soft-tossing lefty. We have a lot of hard-throwing righties. He's a good complement to our pitching staff.''
Vargas is expected to start this weekend against the Chicago White Sox. Zach Eflin, who is scheduled to pitch Friday, has a 10.46 ERA in his last six starts. Vargas could take that spot on regular four days' rest.
Vargas is owed $2,666,667 of his $8 million salary for the remainder of this season, and his contract includes an $8 million club option for 2020 with a $2 million buyout. He receives a $250,000 assignment bonus.
New York agreed to pay $666,667 to the Phillies to offset part of Vargas' 2019 salary, with $333,333 payable Sept. 2 and $333,334 on Oct. 1, and $250,000 to offset the assignment bonus. In addition, the Mets will pay $2 million in 2020 to offset the salary or the buyout.
Philadelphia's commitment will be either $2 million for the rest of this year or $8 million for the rest of this year plus 2020.
''It's too early for us to commit to that,'' Klentak said of exercising the option.
The Phillies were off Monday after losing two of three to the NL East-leading Braves and falling 7+ games behind. But they're only one game behind the second NL wild card heading into a three-game series against San Francisco starting Tuesday.
Vargas' ERA would be second to Aaron Nola on Philadelphia's staff and his WHIP (1.27) would rank first. Opponents are batting just .228 against Vargas despite a fastball that averages just 85 mph.
The Phillies already added a starting pitcher last week when they signed lefty Drew Smyly after he opted out of a minor league deal with Milwaukee. Smyly allowed one run in six innings in a 2-1 win at Pittsburgh on July 21 in his first start and take the mound again Tuesday night against the Giants.
Vargas is 98-95 with a 4.26 ERA in 266 starts and 21 relief appearances with five big league teams. He won 18 games for the Royals in 2017 and was part of their World Series championship team in 2015.
Vargas and Mets manager Mickey Callaway were fined by the team last month for their profanity-filled confrontation with a reporter following a loss to the Cubs at Wrigley Field.
''My first thought was that was so out of character for Jason to be involved in anything like that,'' Klentak said. ''The guy I knew in Anaheim, it's just not who he is. He's not an overbearing personality at all like that. He's very popular in the clubhouse with everybody. He's very likable. On the mound, he's a very hard worker and good teammate. It just didn't add up.''
The 26-year-old Bossart is hitting .195 with seven homers and 28 RBIs at Reading of the Eastern League. He was a 14th-round pick in the 2015 amateur draft from the University of Pennsylvania, where he was a teammate of Bradley Wilpon - a son of Mets chief operating officer Jeff Wilpon and a grandson of Mets owner Fred Wilpon.
The Phillies designated righty Yacksel Rios to make room for Vargas on the 40-man roster. Rios had a 13.50 ERA in four appearances this season.
Klentak said the team is still exploring other trade opportunities. The Phillies could look to add another reliever since David Robertson's status remains uncertain. Robertson hasn't pitched since April because of an elbow injury.
''He continues to progress in his rehab at a slower rate than we had hoped,'' Klentak said. ''The pace of it has been discouraging. We're still hopeful that he may return sometime in August.''
AP Baseball Writer Ronald Blum in New York contributed to this report.
More AP MLB: https://apnews.com/MLB and https://twitter.com/AP-Sports