As Bob Melvin made the slow walk that managers dread, from the dugout to the mound to take a severely bruised baseball from his starting pitcher Sean Manaea, Melvin couldn’t have looked more helpless.

He had burned through four relievers Monday night, unable to find one to douse a scorching Red Sox lineup.

A night later, while the Sox were using the Green Monster for target practice and treating Manaea like a batting practice pitcher, Melvin had to exhaust even more options during a 13-5 rout.

He couldn’t leave his 24-year-old rookie stranded on the mound.

Not after Mookie Betts yanked one of Manaea’s sliders into the Monster seats for a leadoff home run in the first.

“It’s been a while since I’ve pulled a ball,’’ said Betts, who hadn’t gone deep since April 29. “For me to pull it was a plus and then for it to go over the fence was that much better.’’

Ramirez followed three batters later by launching a rocket off the light tower in left-center. Ramirez sent the ball sailing an estimated 468 feet.

“Off the bat, there’s probably not much doubt that that’s got a chance to get out of the ballpark,’’ said Sox manager John Farrell. “The speed in which it exits the bat is impressive.’’

The only blast that traveled farther this year was a 475-foot blast by Giancarlo Stanton.

Ramirez joked, “He got lucky. I’m going to beat it though.’’

The Sox hung five runs on Manaea in a third inning where even the outs were loud. So for the second straight night, Melvin found himself trying to stop a runaway offensive freight train, and couldn’t come up with any answers.

The Sox knew just how much damage they’d done, pouring out hits like cement from a truck.

“When you get a guy out that early, normally that’s kind of the time to feast as a hitter,’’ Travis Shaw said. “When they bring the long guys in, in big lopsided games, those are the guys that you can really do damage on.’’

In two days, Melvin’s thrown every arm he has at the Sox. Only two of them have managed to leave the mound without giving up a run.

After putting up a 15 hits Monday, the Sox matched their season high with 16 last night — and that was without David Ortiz, who got the night off.

Manaea, who was making his third career start, was only the fifth lefty the Sox have seen this season, and they still managed to put up 10-plus hits for the 20th time this season.

In Ortiz’s place, Ramirez went 3 for 4 with two RBIs and three runs scored. His first-inning blast gave the Sox 11 straight games with at least one homer.

After going for three hits Monday, Shaw was 3 for 4 with five RBIs. Chris Young went 3 for 4 with an RBI. Jackie Bradley extended his career-long hitting streak to 16 games (the longest active streak in the majors) with a 2-for-4 night.

Josh Rutledge and Ryan Hanigan were the only starters without a hit.

“I just feel like we all have good approaches,’’ Betts said. “We’re limiting wasted at-bats. When we get an out, we’re working the pitcher some, and when we’re swinging early, we’re hitting the ball hard. That’s what’s key.’’

The overflow of offense made it a pressure-free home debut for Sean O’Sullivan, who went six innings, allowing four runs on 12 hits with three strikeouts in his first start in a Sox uniform.

O’Sullivan got through the first five innings cleanly, only running into trouble in the second inning when he gave up singles to Billy Butler and Marcus Semien. But Bradley made sure it didn’t cost him, fielding a two-out line drive single from Chris Coghlan and firing a dart from center to gun down Butler at the plate and keep the A’s off the board.

With more than enough runs to work with, O’Sullivan picked up his first win of the season.

“Everything we could’ve hoped,’’ Farrell said. “He kept the game in check, the offense did their job.’’

In May alone, the Sox have been a force with 98 hits and 57 runs. Coming into last night, the Sox were hitting .307 since April 20 with an .871 on-base percentage and a .501 slugging percentage — all major-league bests.

They’ve won each of the last six meetings with the A’s, eight of their last 11 overall, moved to seven games over .500 for the first time since 2013, and sit atop the AL East, tied with the Orioles.

The Sox offense has pumped out at least 10 hits in 20 of their first 33 games. The last team in the majors to crank out as many in the same stretch was the 2008 Sox.

Ramirez summed up the reason the offense is churning so well.

“The work that we put in every day, the preparation — not only one guy, everybody,’’ Ramirez said. “You go down in the cage, we’ve got only one batting cage and it’s a long, long line. So everybody’s ready to play every day. Every at-bat, everybody comes with something.

“What we’re doing right now, we’ve got to keep doing.’’

Julian Benbow can be reached at jbenbow@globe.com. Follow him on Twitter @julianbenbow.