PHOENIX -- Casey Schmitt continues to live up to the hype for the Giants.

The 24-year-old infield prospect homered into the second deck at Chase Field while going 4-for-4 with three RBIs to propel the Giants to a 6-2 win over the D-backs in Thursday night’s series opener in the desert.

Schmitt unloaded on a 2-0 curveball from Arizona left-hander Tommy Henry in his first at-bat in the second inning, blasting it 443 feet out to left field for a mammoth two-run shot that knocked in the first two runs of the game.

Schmitt, who is ranked the Giants’ No. 4 prospect by MLB Pipeline, singled in his next two trips to the plate and added an RBI double in the ninth to account for half of the Giants’ eight hits and back another brilliant outing from veteran right-hander Alex Cobb, who worked 7 1/3 scoreless innings to lower his ERA to 1.70 through eight starts, the best mark in the National League.

“He’s almost single-handedly won us two games now,” Cobb said of Schmitt. “Obviously, we put some runs on later, but for a good chunk of that game, it was 2-0, and it was his runs that allowed me to go out and attack and protect the lead. 

“His glove’s never been the question, so seeing him hit, you’re not sure what the hesitation was to bring him up. He looks the part. He acts like a big leaguer. There are certain guys that just fit in a clubhouse. When they put the uniform on and they take at-bats and they take the field, they look like they belong. He checks all those boxes.”

Since making his Major League debut on Tuesday, Schmitt is 8-for-12 (.667) with two home runs and four RBIs, tying Hall of Famer Willie McCovey for the most hits by a Giants player through his first three games since 1901.

“This is just amazing,” Schmitt said. “I’m just kind of taking it all in. I’m enjoying it. It’s a lot of fun.”  

A natural third baseman, Schmitt has made his first three starts at shortstop while filling in for the injured Brandon Crawford. He received plenty of action behind the sinkerballing Cobb, flashing his strong arm when he made a backhand stop up the middle before firing to first base to get the speedy Ketel Marte for the first out of the fourth inning.

Schmitt’s throw was clocked at 92.7 mph, the second-fastest infield assist in MLB this season, behind Pirates shortstop Oneil Cruz (92.8 mph).

The eye-popping play came two innings after Schmitt made an off-balance throw on Christian Walker’s grounder in the hole, allowing Walker to reach on an infield single to lead off the fourth. In between innings, Crawford sat with Schmitt on the dugout steps to go over the play and help his young protégé make an adjustment that served him well on Marte’s grounder.

“He’s been amazing,” Schmitt said. “He’s really helped me out, kind of just learning the position and the hitting side and stuff like that. I like to pick his brain a little bit. … We kind of talked that over. It was funny, I got a ground ball that next inning that was pretty backhand, smooth. Then I looked at him. It was a funny moment.”  

While Schmitt has shown he can handle shortstop, his role is likely to change once Crawford is ready to return from a right calf strain, which will likely happen in the next “24 to 48 hours,” manager Gabe Kapler said on Thursday.

With J.D. Davis and Thairo Estrada both playing at All-Star-caliber levels at third and second base, respectively, the Giants might have a more difficult time keeping Schmitt’s bat in the lineup on a regular basis. Estrada has played some left field in the past, but Kapler said the club would prefer to keep him at one of the middle infield spots given the success he’s enjoyed there this year.

Where does that leave Schmitt?

“I think Casey is going to play some shortstop for us, play some second base, play some third base,” Kapler said. “He’ll move around for us. So far he’s been a really good addition at shortstop, but he has a history of being one of the better third basemen in Minor League Baseball over the last couple of years. It’d be nice to spell both J.D. at third and Thairo at second base.

“I don’t personally think it’s all that important to see the whole road map right now. Just know that he can play those positions for us. We don’t know if someone is going to need a few more days than somebody else, so we want to be cognizant of opening up all the possible doors for him.”