Pirates 4, Cubs 2: Andrew McCutchen had three hits and two RBIs and visiting Chicago continued its offensive woes as Pittsburgh waited out a long rain delay to finish a three-game sweep.

Pirates starter Jeanmar Gomez limited the Cubs to one run on three hits over 3 2/3 innings but was not eligible for the win when he did not return following a 1-hour, 47-minute rain delay. Vin Mazzaro (3-0) was credited with the win after 2 1/3 innings of scoreless relief and Jason Grilli pitched a perfect ninth for his 19th save in as many chances.

Cubs starter Edwin Jackson (1-7) also was done after the delay, but he didn't fare as well before the rain, allowing four runs on six hits in three innings.

McCutchen and Michael McKenry each had RBI singles in the first inning, and Pittsburgh tacked on two more in the second when Travis Snider smacked an RBI triple to center and scored on McCutchen's second hit of the day.

Chicago broke through on Anthony Rizzo's run-scoring fielder's choice in the fourth, right before the heavy rain came, but couldn't continue the rally after the break. Pinch hitter Ryan Sweeney singled home a run in the seventh to make it 4-2, but McCutchen made a sliding catch to rob David DeJesus of a bloop hit and end the threat.

GAME NOTEBOOK: McCutchen has multiple hits in five of his past six games. … Rizzo is 0-for-17 in his past four games. … Jackson is 0-2 against the Pirates this season after entering the year with a 4-0 mark against them.