Pirates swept as offense comes up empty

Derek Shelton is searching for ways to manufacture runs as his team has dropped eight of its last 10 games.

The Pittsburgh Pirates’ offense hit another low Sunday afternoon, when a 28-year-old pitcher who was an undrafted free agent held them scoreless for 5 1/3 innings in his first major league start.

The Pirates looked hapless against San Diego right-hander Stephen Kolek in a 4-0 loss to the Padres, who completed a three-game series sweep before 17,184 at PNC Park.

It was the fourth consecutive...