The Pirates jumped to a 3-0 lead after two innings and had Abad in a 5-1 hole when he was pinch-hit for in the fifth. The Astros got a two-run homer in the ninth from Brandon Laird, but they never threatened most of the game.
"We're having problems getting from that bullpen to the first inning," Astros interim manager Tony DeFrancesco said. "We're down a couple of runs early, down 3-0. It seems like it's the same story and we're battling back again. Today was a big day. I thought we had a chance to win the series and Abad could give us a chance, but unfortunately we were down early again. Kind of frustrating for us."
Abad, who made 30 relief appearances this year before being moved into the rotation, is 0-3 with an 8.03 ERA as a starter. He's pitched 12 1/3 innings in his three starts and allowed 19 hits, 12 runs (11 earned) and walked nine.
"There has to be some way to get out of that first inning without giving up runs early," DeFrancesco said. "Other teams are shutting us down 1-2-3, and we're going to have to make adjustments from the bullpen to the mound. We're going to go with a six-man rotation and he's going to stay in rotation, and hopefully next time out he'll give us a chance to stay in the game."
Pirates starter Kevin Correia (10-8) retired nine of the first 10 batters he faced. Jimmy Paredes led off the fourth with a double and later scored on a single by Brian Bogusevic. The Astros proceeded to load the bases with one out, but catcher Carlos Corporan hit a scorching ground ball to first baseman Gaby Sanchez, who started an inning-ending 3-2-3 double play.
"At least I put it in play and tried to make something happen," Corporan said. "There were two strikes and I was trying to put the ball in play."
Sanchez was thinking about the double play before the pitch was even thrown.
"I knew that if it's hit hard right at me, I can just turn a regular double play," he said. "If the ball is hit to my right side, same thing. A ball down the line would be a tougher double play to second, so the easiest one is to make sure you get one out at home. But we know there's a slow guy running down the line, so [we] might have a chance there."
The Astros wouldn't have another runner past second base until they scored a pair in the ninth. Correia needed only 67 pitches to work six innings, allowing four hits and one run. He struck out one and walked one, which helped his efficiency.
"He was throwing for contact, he did his job," Corporan said. "He was throwing balls and we hit it right at them. That's what it's all about. You pitch for contact and see what happens. He did a good job and he was hitting his spots."
Abad got an out to start the game before the next four batters reached on three singles and a walk, with Garrett Jones and Sanchez banging out RBI singles. An infield hit by Brock Holt in the second inning scored Alex Presley to make it 3-0.
"He made pretty good pitches," Corporan said. "The ground balls just found the hole and there was a broken-bat base hit. We had some tough plays made behind us. I think [Abad] was throwing the ball really well, and he'll improve more and more every outing. He needs to learn how to be a starter."
Presley hit an RBI triple in the fourth to score catcher Rod Barajas from first base, and Presley scored on Holt's sacrifice fly to center to make it 5-1. Presley scored again in the sixth on a perfectly executed squeeze bunt by former Astros shortstop Clint Barmes.
Laird, who came into the game at third base when Scott Moore left with a strained groin, clubbed a Jason Grilli pitch and sent it over the wall for a homer with two outs in the ninth inning to get the Astros to within three runs. It was the first career homer for Laird, who was claimed off waivers from the Yankees on Saturday.
"Everybody always tells me to be ready, and that's what I was," he said. "I went in there and the first at-bat, chased a couple bad pitches, and I just wanted to go up there and see it before I swung. That's what I did, and put a pretty good swing on it."
The ball landed in the Astros' bullpen, so he was able to retrieve it. That was about the only good memory the Astros will take from their final NL game in the Steel City.
"We got the ball and lineup card for him, and he really nailed that ball off Grilli," DeFrancesco said.