Right-hander Luis Castillo was handed an early four-run lead for a second consecutive start and this time responded with six shutout innings, pitching the visiting Cincinnati Reds to a 7-0 victory over the San Francisco Giants in the opener of a three-game series Friday night.

Nick Senzel lashed a two-run triple to highlight a four-run second inning, which turned out to be more than sufficient offensive support for Castillo (4-1) and three relievers.

All four runs in the second off Giants starter Dereck Rodriguez (3-5) came with two outs and were unearned, following a botched fly ball by left fielder Tyler Austin.

After the error and a single by Jose Iglesias, the Reds had two on with two outs before Tucker Barnhart opened the scoring with a single.

Senzel then crushed his triple to center field, making it a three-run inning.

After Joey Votto walked, Eugenio Suarez capped the inning's scoring with a ground-rule double to left field, scoring Senzel.

Rodriguez wound up going five innings, allowing just the four unearned runs and five hits. He walked four and struck out two.

The four-run cushion was identical to the one the Reds had provided for Castillo in his previous start against the Giants last Sunday.

He surrendered that lead in a four-run Giants sixth that featured a three-run homer by Buster Posey. But there was no such rally in the rematch.

Castillo walked the first two batters he faced before retiring three straight to get through a scoreless first, then issued a walk and a two-out double by Stephen Vogt before pitching out of trouble in the fifth.

He was pulled after six innings, having allowed just two hits. He walked five and struck out 11, paving the way for the Reds' second consecutive shutout.

Zach Duke, Michael Lorenzen and Wandy Peralta finished up with three innings of two-hit relief for Cincinnati, which blanked Oakland 3-0 on Thursday.

The Reds tacked on in the ninth on a two-run single by Yasiel Puig and an RBI hit by Kyle Farmer, completing the game's scoring.

Senzel, Suarez and Puig had two hits apiece for the Reds, who scored 37 runs in a four-game home split against the Giants last weekend.

Starting in place of the injured Posey, Vogt had three of the Giants' four hits.

--Field Level Media