Houston, TX (SportsNetwork.com) - Career nights from Chris Heston and Matt Duffy led the way in the San Francisco Giants' 8-1 rout of the Houston Astros in the first-ever interleague meeting between the teams.

Heston (3-3) struck out a personal-best 10 in his first major league complete game, a two-hit masterpiece in which he set down the final 22 Houston hitters after Jason Castro's solo homer in the second inning.

"It was nice to have the opportunity to close it out," Heston said. "That was awesome."

The Astros managed just two baserunners in all, with Jake Marisnick's leadoff single in the first inning the only other blemish on Heston's stellar pitching line.

He was backed by the Giants' highest scoring effort of the season, with Duffy leading the charge by going 3-for-4 and racking up five RBI on a three-run double and a single that brought in two more.

Justin Maxwell added two hits, including an RBI single, and Angel Pagan finished 3-for-5 with a run scored to help the Giants end Collin McHugh's string of 11 consecutive winning decisions.

McHugh (4-1) was hammered for seven runs, though four were unearned due to two Astros errors that opened the floodgates for a five-run fifth inning, and seven hits before being removed after 4 2/3 frames. The right-hander was dealt his first defeat since a 4-2 setback to Miami on July 27 of last season.

Duffy began his memorable night by stepping to the plate with the bases loaded and the game still scoreless in the second inning. The rookie ripped the first pitch he saw from McHugh off the wall in left center to bring in all three runners and give Heston all the support he needed.

McHugh had put himself into the jam by surrendering singles to Brandon Belt and Maxwell, then hitting Brandon Crawford with a pitch while ahead in the count.

Castro's homer brought the Astros within two, but Heston didn't give anything the rest of the way and San Francisco broke the game open with a monster fifth inning.

Singles by Joe Panik and Pagan preceded Buster Posey's sharp grounder that Houston third baseman Luis Valbuena couldn't handle for an error. McHugh fanned Belt for what would have been the third out, but Maxwell followed with an infield hit that wound up scoring two when Marwin Gonzalez threw wildly past second while trying to force out Posey.

"I tried to limit (the damage) but wasn't able to stop the bleeding," McHugh said.

McHugh was then relieved by Kevin Chapman, who was greeted by Crawford's ground-rule double and a two-run single from Duffy that increased the lead to 8-1.

Game Notes

The Giants had scored six runs or less in all 32 previous games to begin the season, the franchise's longest stretch since 1914 ... McHugh remained winless against National League teams, having gone 0-10 in 20 career appearances (14 starts) versus the Senior Circuit ... The Astros had prevailed in each of McHugh's last 11 starts dating back to August of last season ... The Giants have now won seven straight against the Astros, which included a three-game sweep in their last visit to Minute Maid Park back in August of 2012 ... The Astros are expected to activate outfielder George Springer from the 7-day concussion disabled list for Wednesday's finale of this two-game series.