ATLANTA -- Pitching coach Dan Warthen was sure the fifth inning should have been over. He was positive home-plate umpire C.B. Bucknor called two pitches balls that were actually strikes and that Johan Santana, his starting pitcher, should have been walking off the mound after working around a leadoff double.
Instead, the Braves already had one run on the board and were threatening to add more with runners on second and third and only one out. Warthen decided it was time to take a stand. He went to the mound to talk to Santana and when Bucknor arrived to break the meeting up, Warthen aired his grievences about the strike zone. He was ejected.
"At that point in time, it had been going on, it had been building a little bit," Warthen said. "We'd had enough."
The mound visit did little to help Santana. The next four batters all drove in runs, capped by Freddie Freeman's three-run home run deep into the right-center-field seats. The inning powered the Braves to a 6-1 victory and a sweep of the three-game series at Turner Field.
The loss was the Mets' fourth in a row and dropped their record to 3-7 in July. With Sunday's loss, they are 6 1/2 games behind the first-place Nationals. And with a three-game road series against those Nationals beginning Tuesday, manager Terry Collins said the Mets have reached a critical juncture.
"Right now, they're a little down in the dumps at the moment and you can't hardly blame them," Collins said. "We'll give them a day off [Monday] and we've got to start grinding it out in Washington because we'll be in big, big trouble if we play like this there."
What began as a good start for Santana quickly turned ugly in the fifth. Matt Diaz led off the inning with a double and Paul Janish followed with a walk. After Sheets popped out trying to put down a sacrifice bunt, Michael Bourn blooped a double to left field, bringing home the first run.
At that point, Warthen began his fateful trip to the mound. His complaints centered on a 2-2 slider to Janish and a 1-2 fastball to Bourn that Bucknor called balls.
"The inning's over," Warthen said. "Janish is out and Bourn is out. The inning is totally over. And the pitches that [Santana] threw to those guys [Bucknor] had called much worse pitches on our guys."
Warthen contended Bucknor's strike zone was wider with Braves starter Ben Sheets on the mound.
Diaz said while the Braves may have caught a few breaks, the Mets had some calls go their way as well.
"We might have caught some breaks on some pitch calls, but so did they at some point," Diaz said. "We took advantage when we did."
Done in by the fifth, Santana continued a trend for the Mets at the outset of the second half. Their starters this series -- Chris Young, R.A. Dickey and Santana -- combined to allow 16 runs in 13 innings against the Braves.
Collins called the performance of the club's starters this week "shocking." But he and David Wright both said they believe the starters, especially Dickey and Santana, will bounce back.
"There's been more times when they've been good back-to-back, as opposed to where they've struggled," Wright said. "We were a couple pitches away today."
After scoring seven runs in Saturday's loss, the Mets' offense was unable to help out its struggling pitching Sunday. Sheets, who missed two of the last three seasons with injuries and most recently started in the Major Leagues on July 19, 2010, threw six shutout innings. The Mets had no answer for his fastball-curveball combination and managed just two hits and struck out five times.
The Mets' lone run came in the seventh against right-hander Kris Medlen. Scott Hairston doubled, halting a stretch of 11 straight hitters retired by the Braves. Andres Torres brought Hairston home with a two-out single, ending Atlanta's shutout bid.
The Mets have not lost more than four in a row. They'll attempt to continue that trend Tuesday against the Nats, a series Wright knows is beginning at a critical time."
"This is not good coming out of the break," Wright said. "But, like I said, I think we had a couple opportunities to win a few of these games. We just couldn't pull through. Washington will be a good challenge for us."
Teddy Cahill is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.