Musgrove (3-3), a 2011 graduate of Grossmont High in suburban El Cajon, was facing the Padres for the first time in his three-year big league career. He allowed seven singles while striking out five and walking two.
The Padres had runners on first and third after hitting consecutive singles to open the seventh but Musgrove retired the side, including inducing Manuel Margot to hit into an inning-ending double play.
He was relieved by Steven Brault, a 2010 Grossmont grad. Brault had a short night, allowing two runs on two hits while getting just one out in the eighth.
The Pirates won for the third time in nine games and the Padres lost for the 10th time in 12 games.
Musgrove was the starting pitcher for the United States in the All-Star Futures Game at Petco Park on July 10, 2016. He made his big league debut that Aug. 2 for Houston against Toronto, which drafted him with a supplemental first-round pick in 2011 before trading him to the Astros the following year. Musgrove was the winning pitcher in Game 5 of the World Series for Houston, which traded him to Pittsburgh in January in the deal for Gerrit Cole.
While Musgrove dominated, the Pirates piled on against rookie lefty Eric Lauer (3-5) and the Padres. The Pirates scored an unearned run in the first inning on two singles and Austin Hedges‘ passed ball, and added four runs, including two unearned, in the third. Hedges and shortstop Freddy Galvis each had a throwing error. Gregory Polanco hit a two-run double and was thrown out to end the inning trying to stretch it into a triple. Josh Bell hit an RBI triple and Elias Diaz drove in a run on a fielder’s choice.
Mercer homered to center field leading off the fourth to make it 6-0. It was his fifth.
Lauer allowed six runs, three earned, on nine hits in five innings, struck out three and walked none.
Padres manager Andy Green was ejected before the top of the fourth inning by plate umpire Angel Hernandez. Green apparently was unhappy about a balk call against Lauer while trying to pick off Polanco in the second. The Pirates did not score that inning.
Pirates: Placed RHP Chad Kuhl on the 10-day disabled list with a right forearm strain.
Padres: Green said OF Franchy Cordero is leaning toward having surgery to remove a bone spur from his right elbow.
Pirates: RHP Trevor Williams (6-5, 4.03), a 2010 graduate of San Diego’s Rancho Bernardo High, is scheduled to start the middle game of the series. He’s made one career start against the Padres, giving up four runs in six innings and getting a no-decision in an 8-5 Pirates loss at Pittsburgh on May 20.
Padres: LHP Joey Lucchesi (3-3, 3.57) is scheduled to make his third start since returning from a DL stint that lasted just more than a month.