SEATTLE — Of all the superlatives making the rounds about Gary Sanchez, Starlin Castro probably best captured the prevailing feeling about the rookie in the Yankees’ clubhouse.

“That’s Babe Ruth right now,” Castro said with a laugh. “Nobody can get that guy out. And when he gets out, it’s line drive. It’s really fun to watch. Even catching, nobody can run on him. It’s pretty awesome.”

Castro spoke late Monday night after the Yankees’ 7-5 loss to the Mariners, a game in which the second baseman happened to hit two home runs.

But that accomplishment was relegated to sidebar status as Sanchez had three hits in his first three at-bats, including two home runs. His sixth-inning homer gave him eight homers in his last 38 at-bats.

Sanchez, who has a .560/.621/.1.360 slash line, with six homers and nine RBIs in his previous seven games entering Tuesday night, became the first player in Yankees’ history to hit at least eight homers in his first 19 career games. Only seven major leaguers have achieved the feat since 1900, including Trevor Story of the Rockies earlier this season. Before Story, the last to do it was George Scott of the Red Sox, who homered nine times through 19 games in 1966.

“It’s almost like it’s easier for him here,” said Mark Teixeira, who has seen plenty of young players over the years struggle in adjusting to the big leagues. “He’s more focused, he’s got more energy, he’s hitting balls further. You don’t see that very much. You don’t see guys just kind of come up here and make the game look easy in the big leagues in the first couple weeks, and he’s doing that. It’s impressive.”

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And, as Castro alluded to, Sanchez behind the plate has been almost as impressive. The 23-year-old, whom Joe Girardi started at DH Tuesday, on Monday threw out Shawn O’Malley trying to steal, making Sanchez 5-for-7 in throwing out runners.

“I don’t know if I’ve seen an arm on a catcher like that in a while,” Teixeira said.

The 36-year-old recalled his first spring training with the Rangers in 2002, when cannon-armed Ivan “Pudge” Rodriguez was in his final season with Texas.

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“He was throwing BBs as one of the best catchers to ever play the game,” Teixeira said of Rodriguez. “But that [Sanchez’s] arm is right up there with Pudge’s when he was in his prime. That’s something to say . . . you better make sure you can get there because if he has any chance to get you, he’s going to get you.”

Sanchez’s performance has not surprised those who played with him much of the season in Triple-A Scranton/Wilkes-Barre. Chad Green, a recent addition to the rotation, is one of them.

“We’ve been seeing that all year in Scranton, so I guess it doesn’t really come as a shock to the guys that have seen him play all year,” Green said. “I guess when he comes out this hot, it’s a little surprising but . . . like I said, nobody’s really surprised, but it’s good to see him do this at this level.”

Girardi said it was difficult to take Sanchez out from behind the plate Tuesday, even though he was able to keep his bat in the lineup as the DH. The manager, with a smile, said he’ll give Sanchez a full day off “on Thursday,” an off day for the team.

“I mean, it is [difficult to rest Sanchez],” Girardi said. “He’s playing himself into playing every day is what he’s done. It’s been impressive. You can’t say any more about him.”