DeSclafani (4-1), who signed with the Giants after five seasons in Cincinnati, was outstanding in his first appearance back at Great American Ball Park, scattering six hits and striking out seven.
"I felt like today I definitely had to grind, make pitches," DeSclafani said. “I didn’t feel like I was ahead of a lot of guys. I'm just glad I was able to make the pitches when they mattered.”
Jake McGee pitched the ninth and got the Reds in order for his 11th save.
Brandon Crawford hit his team-leading 10th homer for the NL West-leading Giants, who took the first two of the four-game set with the Reds.
Luis Castillo (1-6) struck out 11 through five innings and gave up three runs, all on Dickerson's homer.
With Crawford and Mauricio Dubón on base in the Giants fourth, Castillo threw a 1-1 changeup that Dickerson hammered over the right-field fence, one of his three hits in the game.
“(DeSclafani) gave up the leadoff home run, but he continued to attack the strike zone,” San Francisco manager Gabe Kapler said. “If you attack the strike zone against good hitters, you’re going to get hit, but you have to get right back in the strike zone.”
Despite the Reds winning just one of Castillo's first nine starts, he said Tuesday's outing was “three steps forward” for him. Prior to that, he'd been having a rough May, having allowed 17 runs in 13 innings.
“The results were there," he said through a translator. “The biggest difference today was my change up. Before I was leaving it over the plate. Tonight I was getting it below the zone.”
The Giants have been in first place in the NL West for 22 straight days. According to STATS, that's their longest run of consecutive days at the top of the division since a 93-day streak in 2016. San Francisco spent only three days in first place from 2017-2020.
PACK ’EM IN
The Reds will return Great American Ball Park to full capacity on June 2 as the state of Ohio loosens COVID-19 restrictions. That will be a 12:35 p.m. EST game against the Philadelphia Phillies. Crowds have been limited to about 12,000 so far because of the state rules on gatherings.
DeSclafani's battery mate, Curt Casali, played for the Reds for three years and also was making his first appearance back in Cincinnati. Wednesday’s scheduled starter, Kevin Gausman, as well as Thursday’s, Johnny Cueto, also are former Reds.
“Any time you come back and face your old teammates, there's going to be a lot of nerves,” DeSclafani said.
Giants: 2B Wilmer Flores left the game in the second inning with tightness in his right hamstring. He'll get further evaluation Wednesday, Kapler said. ... 1B Brandon Belt missed a third straight game with tightness in his left side. He is day to day.
Reds: The absence of two key players due to injuries caused another ripple in an infield already struggling defensively. Mike Moustakas was held out of the starting lineup for a fourth game with a heel contusion, and Nick Senzel was out with a sore knee and other minor injuries. Moustakas, the regular third baseman, had been playing first base with Joey Votto sidelined, and outfielder Senzel had been at third.
LHP Wade Miley (4-3), who threw a no-hitter on May 7 but lasted only three innings in his last start Friday, will be on the mound for the Reds against Giants RHP Kevin Gausman.
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