PITTSBURGH — Pedro Alvarez hit his second home run of the day, Charlie Morton pitched seven solid innings and the Pittsburgh Pirates beat the Colorado Rockies 5-1 to split a doubleheader on Wednesday.
Colorado broke up James McDonald's no-hit bid in the seventh inning of the opener on its way to a 2-1 win.
Alvarez helped Pittsburgh's tepid offense tie a season high in runs in the second game, hitting a solo shot down the right-field line off Jhoulys Chacin (0-2) to cap a five-run fifth.
Morton (1-1) benefited from an offense that broke out of a season-long slump, at least for an inning.
Garrett Jones went 3 for 4 in the nightcap, including a two-run shot off Chacin as baseball's lowest scoring offense gave its pitching staff some help.
Despite the outburst Pittsburgh set a major league record by playing its 18th straight game starting the season in which neither team scored more than five runs, surpassing the standard set by the 1943 Detroit Tigers.
The Pirates began the day dead last in the majors with 36 runs scored. They've managed to hang around thanks to a pitching staff second in the National League in ERA (2.72).
Pittsburgh wasted another outstanding effort in the opener. McDonald ended up with a no-decision after the Rockies scratched across two runs — on just three hits — to win.
Morton appeared in danger of the same fate. He cruised through the first five innings but the game remained scoreless until the bottom of the fifth when Pittsburgh got to Chacin.
Alex Presley doubled with one out and Nate McLouth send a fly ball to left that Colorado's Carlos Gonzalez lost in the late afternoon sun. Gonzalez stuck out his glove but the ball landed just in front of it for an RBI double.
Andrew McCutchen followed with an RBI single, just the second time all season the Pirates have had a two-run lead with their starting pitcher in the game.
It didn't stay 2-0 for long. Jones hit his third home run and Alvarez — whose average jumped from .108 to .156 on the day — clanged Chacin's offering off the pole in right for his fourth homer of the season.
Morton didn't let the surprising cushion go to waste. Ramon Hernandez provided Colorado's only run with a solo homer in the seventh. But other than that Morton was effective, striking out two, walking one on 100 pitches.
The win helped take some of the sting out of another difficult loss in the opener after McDonald flirted with the first Pirates no-hitter since Francisco Cordova and Ricardo Rincon combined over 10 innings against the Astros on July 12, 1997.
McDonald was nearly flawless before Troy Tulowitzki's infield single with one on in the seventh. McDonald gave up one run and one hit in seven innings, striking out eight and walking three.
Matt Reynolds (2-0) won in relief of starter Juan Nicasio. Rafael Betancourt worked the ninth for his sixth save.
Chris Resop (0-2) lost after relieving McDonald in the eighth.
Resop hit pinch-hitter Eric Young with a pitch, Marco Scutaro singled and. Tyler Colvin followed with a sacrifice fly off reliever Tony Watson, and Young just beat Jose Tabata's throw to the plate.
NOTES: As part of the new collective bargaining agreement, both teams were allowed to add a roster spot for the doubleheader. The Pirates recalled reliever Jared Hughes from Triple-A Indianapolis while the Rockies brought up reliever Zach Putnam. Hughes pitched a scoreless ninth for Pittsburgh ... The Pirates are off Thursday then begin a six-game trip on Friday in Atlanta. A.J. Burnett (1-0, 0.00 ERA) will face Tommy Hanson (2-2, 3.38 ERA). ... The Rockies are also off Thursday and start a three-game set against the Mets on Friday. Drew Pomeranz (0-1, 6.75 ERA) will start for Colorado. The Mets had not announced a starter.