Miami entered Wednesday just 4-12 this month after setting a franchise record with 21 wins in May. Over the last three years, Miami is 51-35 in May, compared with 20-50 in June.
Manager Ozzie Guillen wasn't around for the Marlins' club-worst 5-23 record last June, but he's been caught off-guard by his team's performance this month after a red-hot May.
"It surprised me how good you can be one month and then so bad right after," Guillen said. "We know we're not performing. It's not a secret for anybody in this ballclub. Everybody who wears this uniform knows we're not performing."
The Marlins are averaging 2.50 runs per game in June and have lost 11 of their past 13 games. Still, Guillen believes his club can turn it around.
"The energy is there, the effort is there, we just can't get it done," the manager said. "I'm not going to turn my back on these guys. Nope. We're not playing good but we're good. We've got talent. I think I believe in this ballclub. There's a lot of guys we think could have a better year or better month, they're not doing it."
Miami entered Wednesday's game vs. the Red Sox with a 33-34 record. It's the first time the team has been below .500 since May 5, when it was 13-14.
Guillen has been in constant contact with owner and CEO Jeffrey Loria, but the manager doesn't think the Marlins need a shakeup just yet.
"Yeah, I talked to Jeffrey, I talk to everyone, maybe too many times," Guillen said. "But what are they going to do? I just say stick with it. It's still early. I always say you don't win the pennant race in April, May and June, but you can lose it. We've got to believe in what we have.
"What are we going to trade a guy? When you trade one guy to help, how about the rest of the eight [starters]? We can't trade eight guys. I think everybody here has talent. I think everybody here has done it before. And I think everybody here will come out of this."