Harrison had four hits, including a tiebreaking homer, to help the Pirates beat the Colorado Rockies 7-5 on Sunday.
Harrison was a big part of avoiding a third straight loss. He homered on the first pitch of the eighth to break a tie, but his work on the basepaths in the sixth was nearly a carbon copy of a play against the New York Mets on June 27.
After Snider's two-run homer tied it, Harrison singled. He swiped second but was caught in a rundown when he slid past the bag. He survived to reach third -- giving him two stolen bases on the play -- and scored on a pinch-hit double by Ike Davis to make it 5-4.
"As I got off, I was like, `It's easy for me to try to make something happen as opposed to trying to reach back to second because he was right there.' And something happened," he said. "More and more I got into it, I was able to kind of set up some moves to where I might be able to be safe."
The Rockies had him caught but couldn't finish the play when catcher Wilin Rosario tripped and dropped the ball.
"We've got to get an out there," manager Walt Weiss said. "I look at a rundown as a free out. Harrison's one of the tougher guys to put away in a rundown but we've got to get the out there. It was a good play."
Harrison's teammates were impressed with his footwork.
"It's just athleticism," Davis said. "I don't know how you do it, but he's done it, he's good at it. I wish I had that in the bag."
"If we won today we would have gone 4-2 on the homestand but it is what it is," Arenado said. "We were able to split and we won the series."
Arenado tied it 5-5 with a homer in the seventh, his ninth of the year and second in as many games before Harrison and Polanco struck in the eighth off reliever Rex Brothers (3-5).
"I was looking for a pitch I knew I could get (the) barrel on," Harrison said. "He threw a pitch that was probably middle, I could either pull or hit the other way. I was able to barrel it to right-center."
Pittsburgh starter Edison Volquez has struggled against Colorado and at Coors Field. He entered Sunday 3-8 with a 7.80 ERA in 13 career starts against the Rockies. The numbers are even worse in Denver where he was 1-5 with a 8.45 ERA in eight career starts.
He didn't improve those statistics Sunday. He allowed an RBI single to DJ LeMahieu in the second inning and a two-run homer to Barnes as part of a three-run fourth inning, although only one of the runs was earned.
He left after loading the bases with one out in the fifth. Reliever Jared Hughes got Barnes to hit into an inning-ending double play.
"Bases loaded there, I'm really thinking, `Hey, put it in play.' The best way to do that is to throw strikes," Hughes said. "That's what I did. I went out there and got ahead in the count and our defense made a good play."
Rockies starter Franklin Morales didn't fare any better. He labored through four-plus innings, allowing two runs on six hits and walking five. He left after issuing two walks to leadoff the fifth. The Rockies got out of a bases-loaded, no-out jam when Arenado snared Jody Mercer's liner and tagged third for a double play and Neil Walker grounded out.
"Good play by Nolan. He had some big hits, Barnes had a big hit," Weiss said. "There were some things that made you think we would put that game away."
Rockies SS Troy Tulowitzki (left hip flexor strain) flew to Philadelphia on Saturday to have his hip checked by Dr. William Meyers. Meyers operated on Tulowitzki's injured groin in 2012. Tulowitzki was spotted in the stands behind home plate at Yankees Stadium on Sunday. ... Pirates 3B Pedro Alvarez returned to the lineup after not starting the past four games. ... Pittsburgh RHP Vance Worley (3-1, 3.10 ERA) will start Monday's series opener in San Francisco. ... Colorado LHP Yohan Flande (0-2, 7.20) will start against the Cubs in Chicago on Monday.