Neil Walker hit a walk-off home run off Chicago Cubs reliever Carlos Villanueva to give the Pirates a 1-0 victory against the Cubs in 10 innings on opening day at PNC Park Monday.

Walker worked a full count before hitting a changeup into the seats in right field. The home run ended 10 innings of offensive struggles against Cubs starter Jeff Samardzija.

The Pirates got what they hoped for from Francisco Liriano, who completed six scoreless innings. He allowed four hits, walked three and struck out 10.

Liriano made the second opening-day start of his career. His first came in 2009 with the Minnesota Twins against Seattle Mariners ace Felix Hernandez.

After striking out the side in the fourth inning, Liriano had eight on the day, including Anthony Rizzo and Mike Olt twice. Cubs center fielder Emilio Bonifacio singled twice and Welington Castillo walked, but no runner moved farther than second base.

The Cubs threatened in the fifth. Nate Schierholtz led off with a single and Darwin Barney walked on four pitches. Jeff Samardzija tried to bunt the runners over, but bunted right back to Liriano. Liriano threw to Pedro Alvarez for the force at third and Alvarez had enough time to throw out Samardzija at first for a double play. The play withstood a challenge by Cubs manager Rick Renteria.

Liriano allowed the Cubs to start the sixth inning the same way they started the fifth, with a single by Junior Lake and a walk from Starlin Castro. Liriano then struck out Anthony Rizzo for the third time, forced Mike Olt to pop out and struck out Welington Castillo to end the inning.

Emilio Bonifacio doubled off Mark Melancon to start the eighth and took third base on Junior Lake’s sacrifice bunt. With the infield drawn in, Starlin Castro grounded to second base, starting a 4-2-5-1-6-5 rundown. Melancon threw a cutter in on Rizzo’s hands to induce an inning-ending weak pop-out.

The Pirates didn’t put a man on second base until the fifth when Travis Ishikawa singled and advanced on a ground ball.

Starling Marte doubled to lead off the seventh and Andrew McCutchen walked with one out. The Cubs shifted on Pedro Alvarez, who lined a ball back up the middle, and turned an inning-ending double play.

Instant replay was used twice in the game and both times the ruling favored the Pirates. Umpires in the New York City-based replay command center confirmed a double play call and overturned a pickoff, giving the Pirates an extra out on both occasions.

First Published: March 24, 2016, 5:10 p.m.