OAKLAND, Calif. (AP) Pirates manager Clint Hurdle was in the clubhouse relaxing when his bullpen put the finishing touches on the team's third come-from-behind win in three days.
With their relievers pitching so well lately, the Pirates are ready for a four-game series with NL rival St. Louis beginning Monday.
Adam Frazier tripled in the tying run with one out in the sixth, then scored on an infield single to lift the Pirates to a 6-3 victory over the Oakland Athletics on Sunday.
Four Pittsburgh relievers combined to retire the final 12 batters, extending the bullpen's scoreless streak to 32 2/3 innings.
''The guys in front had to deal with some traffic today and they stayed focused on making the next good pitch,'' Hurdle said after the Pirates' seventh win in nine games. ''They all just stayed within themselves, kept their composure and competed with the skills that they had. It worked out well for us.''
Hurdle wasn't around to see it on the field. He was ejected in the bottom of the sixth for arguing balls and strikes.
The A's scored twice in the second but managed only one run the rest of the way, despite getting men on base in five of the final six innings.
A.J. Schugel pitched out of a one-out jam in the sixth with runners on the corners. Neftali Feliz retired three straight in the seventh after giving up consecutive singles. Tony Watson got a double play to end the eighth following a one-out single by Yonder Alonso before Mark Melancon pitched the ninth for his 24th save, preserving Francisco Liriano's first win in more than five weeks.
''When you have one of those days when you don't have your `A' game, it's nice to know that the bullpen is going to do a great job,'' said Liriano, who allowed three runs and six hits with two strikeouts and one walk. ''They've done a great job the last couple of years and this year, too.''
David Friese hit a two-run homer and Gregory Polanco added two RBIs as the Pirates completed the three-game sweep in their first visit to the Oakland Coliseum since 2010.
Liriano (5-8) pitched five innings to win for the first time since May 24. The lefty had lost five straight games before beating the A's to help extend Pittsburgh's winning streak to four.
Billy Butler had an RBI double and scored for Oakland. The A's have lost four straight after winning the opener on this five-game homestand.
''We got derailed again this series,'' Oakland manager Bob Melvin said. ''It's frustrating but no more for me than anyone else.''
John Jaso had two hits for Pittsburgh to snap a 0-for-10 skid. Jaso was also hit by a pitch in the fifth before Polanco's two-run single.
Friese, who entered the game as a pinch hitter in the sixth, homered off John Axford in the eighth.
Matt McBride was called up from Triple-A Nashville to replace injured Oakland backup catcher Josh Phegley on the roster but didn't arrive at the Coliseum until shortly before first pitch. He started and batted eighth, going 1 for 2 in two plate appearances before getting lifted for a pinch hitter in the sixth.
Pirates: OF Andrew McCutchen took the day off to rest his sore left heel. McCutchen was injured while sliding into home plate on a wild pitch Friday.
Athletics: Reliever Francisco Rodriguez left the game with a right shoulder strain after facing one batter in the eighth. He is scheduled to have an MRI. . Phegley was placed on the disabled list with what team officials are calling a right knee strain. Melvin said it's possible that Phegley will require surgery.
Pirates: Jonathon Niese (6-6) takes a four-game losing streak into Monday afternoon's start in St. Louis. The lefty has a 5.32 ERA on the road this season.
Athletics: Right-hander Kendall Graveman (3-6) pitches the series opener in Minnesota on Monday. Graveman has allowed two runs or less in six of his previous eight starts.