DENVER -- Turn. Peer incredulously to the sky. Turn to the umpire and accept a new baseball.

On Tuesday night, right-hander Antonio Senzatela became the latest Rockies starting pitcher to do this dance of despair as the Giants tagged him for three home runs in a 14-4 loss at Coors Field.

Rockies starting pitchers have given up homers in 12 straight games. Senzatela -- who yielded an Evan Longoria solo shot in the second, and Mac Williamson’s three-run homer and Kevin Pillar’s two-run shot in the fourth -- turned in the seventh multihomer bummer in those 12 games.

• Box score

“When a team goes well, you hear managers, coaches, organizations say, ‘Hey, our starters got on a roll. They gave us a chance to win every night,’” Rockies manager Bud Black said. “And if we start to pitch, we’re going to rattle off some wins. But until that consistency in the rotation happens, it’s going to be a little uneven. So we’ve got to get that.”

After two straight postseason trips based on solid starting pitching, the starters are suddenly a problem.

The Rockies have averaged 6.8 runs per game over the last dozen, and tallied seven or more runs eight times, yet are just 6-6 over that stretch. And four games into a nine-game homestand within the National League West, starters Tyler Anderson (2), Kyle Freeland (3), German Marquez (2) and Senzatela have seen 10 balls become souvenirs. The Rockies are now 1-3 in a stretch that should be a good time to gain ground in the division given the schedule.

On Tuesday, the Rockies' offense managed to hit two leadoff home runs off Madison Bumgarner, and received two triples from Ian Desmond, but the offense is having a hard time keeping up in this unwanted Home Run Derby.

Senzatela lost command of the strike zone with two outs in the fourth, as Brandon Belt doubled, Evan Longoria walked and Williamson homered to put the Giants up 4-1 in his season debut. The bleeding, however, didn't stop there. Before Senzatela could escape the frame, Brandon Crawford singled and Kevin Pillar hit his sixth dinger of the season. The right-hander gave up seven runs on eight hits, and struck out three.

The variances in the struggles of the rotation this homestand are slight. Anderson, now at Triple-A Albuquerque, fell into a predictable pitch mix, with poor location. Freeland, in two starts since missing time with a blister on his left middle finger, is not finishing pitches, which means they stay high and don’t go to the corners. Marquez, who was saved by his team’s late comeback in his last outing, had one Coors Field floater, and another when he missed location by the width of the plate and didn’t put a changeup low enough. Senzatela's issues were similar.

“It’s a common theme -- ball up,” Black said. “You look at the homers. Longoria, fastball up, out over the plate; he tried to go down. The ball to Williamson was a hanging breaking ball, up. The ball to Pillar, up.

“Charlie Blackmon’s homer, up. Iannetta, up. Gotta get the ball down."

Black said Senzatela didn’t have the proper finish on the pitches, possibly “trying to make a really good breaking ball harder, better,” and achieving neither. Senzatela concurred.

“I feel, in my mind, I try to make a nasty pitch, and I just leave it right in the middle,” Senzatela said. “I think that good outings are coming. Bad week for us. It’s OK. We’ll go get them."

Issues and answers

Issue: All but one of the Giants’ 14 runs came with two outs in the inning -- though the homers did at least cease after Senzatela left the game. The seven runs not charged to Senzatela came off Seunghwan Oh (two) and DJ Johnson (five).

Answer: “I don’t think it’s mental,” Black said. “It’s just a matter of pitch execution, making the pitches."

Issue: Oh saw his ERA balloon to 7.90 after his rough inning. He put himself in trouble by walking the eighth-inning leadoff man. And with two down and two on, Oh could do nothing but pocket a softly hit ball off the bat of Joe Panik. Steven Duggar then singled in two runs.

Answer: “The walk always is not advisable, but a couple soft singles. … He’s in a bad rut right now,” Black said. “He’ll come out of it. He’s too accomplished a pitcher, the stuff’s still solid. It’s going to be 55-60 appearances, and at the end of all this, if he stays healthy, I think you’re going to see good results."

Tapia stays hot

Raimel Tapia, whose dramatic triple helped turn Sunday’s game against the D-backs, went 3-for-4 with two hits off Bumgarner. He has shown well by hitting .308 in his last 17 starts, and notching 14 hits in that span.

“A good pitcher like Bumgarner, it’s fun to face him because I know to be a good hitter you’ve got to bring your A-game every day,” Tapia said in Spanish, through a translator. “In order to stay in the lineup, I’ve got to face those guys, and I appreciate those times."