SEATTLE — Rafael Devers was so excited he could barely walk when he got back to the dugout after rounding the bases in the third inning.

The 20-year-old Red Sox rookie had just homered for his first major-league hit.

“It was surreal,” he said after Boston’s 4-0 win in Seattle on Wednesday.

Devers, the youngest player in the majors by 73 days (the Dodgers’ Julio Urias is the second-youngest), has hardly looked rattled in his first two days with the Red Sox.

On Tuesday night, Devers debuted and went 0 for 4 but drew two walks and made a handful of impressive plays in the field.

On Wednesday he collected his first two hits, the home run in the third and then a single up the middle off a left-handed reliever in the seventh.

Devers became the youngest Red Sox player to homer since Tony Conigliaro in 1965. He was also the first Red Sox player to record a home run as his first hit since Daniel Nava in 2010.

“The only time I felt a little uncomfortable was in the first inning of (Tuesday’s) game,” Devers said. “Ever since that inning passed by, I’ve felt very comfortable.”

“He’s got something special in that bat,” Red Sox Manager John Farrell said. “This is not an easy ballpark to hit a ball out to center field regardless nighttime, daytime, well-struck, then he gets the left-hander and stays in the middle of the field for the line drive. So he’s been impressive in the two days he’s been on the field, last night defensively and today offensively at the plate.”

The Red Sox have yet to announce their plans for Devers following the acquisition of third baseman Eduardo Nunez, but Devers seems to have provided a spark to Boston’s offense.

“He hasn’t hurt his cause by any means with what he’s done in a very short look,” Farrell said. “We’ve talked quite a bit recently about the need to get offense and today is a display of what he’s capable of doing so he’s taking care of what he can on his end.”

Devers, who played 77 games for the Double-A Portland Sea Dogs and just nine games in Triple-A Pawtucket before his promotion, said he’s tried not to think about what he needs to do to stick in the majors.

“I haven’t really thought much about what’s to come but the way I’ve always been, wherever they put me to play, I’m going to give 110 percent and the cards are going to fall where they may,” Devers said.

“It’s been less than 24 hours that he’s been on the field but it’s been positive results, it’s been great contribution on his part,” Farrell said. “You know what, he looks very much at ease whether defensively or in the box.”

OVER THE COURSE of his eight-year career, Chris Sale has been slightly better in the first half with a 2.74 ERA and .208 average against in the first months of the season compared to a 3.22 ERA and .238 average against in the latter months.

This year seems different.

In three starts since the break, Sale has yet to allow a run.

The 28-year-old dazzled once again on Wednesday against the Mariners, allowing just three hits and a walk over seven scoreless innings. He struck out 11, bumping his major league-leading strikeout total to 211.

“We’re watching one of the better years ever pitched by a major league pitcher in the American League and we’re fortunate it’s in our uniform,” Farrell said after Boston’s 4-0 win.

In three starts since the All-Star break, Sale has allowed just 10 hits and five walks while striking out 33 batters in 202/3 innings.