Boston Red Sox's Xander Bogaerts, center right, celebrates his grand slam that also drove in Mitch Moreland (18), Hanley Ramirez, behind and J.D. Martinez, right, during the third inning of a baseball game against the Kansas City Royals in Boston, Monday, April 30, 2018. (AP Photo/Michael Dwyer)
Boston Red Sox's Xander Bogaerts, center right, celebrates his grand slam that also drove in Mitch Moreland (18), Hanley Ramirez, behind and J.D. Martinez, right, during the third inning of a baseball game against the Kansas City Royals in Boston, Monday, April 30, 2018. (AP Photo/Michael Dwyer) Credit: ap — Michael Dwyer

Boston — Xander Bogaerts hit a grand slam over the Green Monster and the Boston Red Sox finished April with their most wins ever by beating the Kansas City Royals, 10-6, on Monday night.

Mitch Moreland hit a solo homer and had three hits along with Bogaerts for the Red Sox, who posted their 19th victory in April. They had reached 18 three times, the last coming in their World Series-winning 2013 season.

Whit Merrifield had three hits and two RBIs for the Royals, who were coming off their first consecutive wins this season.

Hector Velazquez (4-0), the first of three relievers, worked two scoreless innings of relief for the victory.

Trailing 3-0, Boston scored a run in the second on Moreland’s homer and five off Jason Hammel (0-3) in a third inning highlighted by Bogaerts’ slam that completely left Fenway Park. Moreland drew a bases-loaded walk for the other run.

It was Boston’s sixth slam of the season, tying the then-Montreal Expos from 1996 for most ever in the majors by May 1.

Boston fell in the 3-0 hole in the first when starter Eduardo Rodriguez gave up three runs on three walks, two singles and a hit batsman.

The Royals made a late lineup change, which caused confusion in the press box when everyone thought the club had moved its DH to third base after Moustakas had to leave in the first.

It would have forced pitcher Hammel to hit.

The problem was: The Royals had given a new lineup to the umpires from the one posted in the press box and on Fenway’s scoreboards that had Moustakas at third base and Cheslor Cuthbert as the DH. Cuthbert came in at third base at the bottom of the first.

Both starting pitchers were out by the fifth inning.

Rodriguez gave up five runs, walked three, hit two batters and struck out six in four.

Hammel was tagged for eight runs on eight hits in 4⅔innings.

The Royals’ traveling party had 28 extra guests because they were invited to bring their dads or brothers on the trip.

“I really, really enjoy it — a chance to come to Fenway. They went on a tour here, a private tour. I think they all enjoyed that,” manager Ned Yost said. “It’s just a phenomenal trip together being able to share three days like this.”

Trainer’s Room

Red Sox: Manager Alex Cora decided to give OF Mookie Betts a second straight day off because of a tight right hamstring that forced him out on Saturday. “I feel like not starting today is going to benefit him, but if we need it late in the game, we’ll use him,” Cora said.

Up Next

Royals: RHP Jakob Junis (3-2, 3.34 ERA) hopes to rebound tonight from a miserable previous start when gave up a club-record tying five homers against the White Sox.

Red Sox: LHP Chris Sale (2-1, 2.31) looks to continue his strong run, having allowed three or fewer runs — one or less four times — in his initial six starts.