BOSTON -- Star rookie Kristian Campbell again is not in the Red Sox lineup Monday.

The Red Sox and Mets will play the first game of their three-game series at Fenway Park at 6:45 p.m. Boston manager Alex Cora is skipping the game to attend his daughter's Boston College graduation.

It's unclear as of now why Campbell is not in the lineup for a second straight day. He didn't play Sunday in a 10-4 loss to the Braves. Bench coach Ramón Vázquez should provide some clarity when he speaks at 3:45 p.m.

Campbell has struggled of late though. He is just 4-for-51 (.078) with one home run in his past 12 games dating back to April 30.

"It feels like sometimes he's in between the breaking ball and the fastball," Cora said Friday. "Just a kid that went off the first month of the season and people are gonna start making adjustments. So now it's our time to make the adjustment. And for some, especially as a young kid, like he's gonna take longer than others. But I truly believe that the quality of the at-bat is still there. He's still swinging at the right ones. He's not chasing too many pitches. He's swinging and missing more than we thought. But obviously it's still the big leagues. We have faced some great pitching the last two, two and a half weeks. So he'll get it going."

Right-handed rookie Hunter Dobbins (2-1, 3.90 ERA) will start for Boston opposite right-hander Kodai Senga (4-2, 1.02 ERA).

The 32-year-old Senga has allowed five earned runs in 44 ⅓ innings (1.02 ERA). He's held opponents to a .210 batting average.

Senga's second most used pitch is a ghost forkball. Opponents are 5-for-59 (.085 batting average) with just one extra-base hit (a double) against it.