Letting games get away late "not who we are," Peter Vermes says of Sporting KC's latest disappointment

KANSAS CITY, Kan. – Two matches into the MLS season, and it’s already getting old for Sporting Kansas City.

Twice in as many outings, Sporting have taken a clean sheet into the 90^th minute. And both times, they've seen it evaporate because something went wrong in the back.

“It's unacceptable,” manager Peter Vermes said in his postmatch news conference on Saturday night, after Matt Hedges' 90^th-minute set-piece header delivered FC Dallas a 1-1 draw and a road point at Sporting Park while keeping the defending MLS Cup champions winless in MLS play. “It's not who we are. I'm not happy, and the guys know it. It's not who we are.”

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Sporting have proven that in the CONCACAF Champions League quarterfinals, locking down Mexico's Cruz Azul in a 1-0 first-leg victory on Wednesday. So what's going wrong in the league matches?

“It's a lot of things,” center back and captain Matt Besler said. “Any time plays happen like that, you can look at it and dissect it, and there's a number of reasons why they happen. But for us as a team, we have to lock a game down. Right now, the first five minutes of each half and the last five minutes of each half, they're not good enough for us as a group.”

Besler refused to blame Sporting's ever-shifting lineups – the consequence of a 15-day, five-match stretch to open the season – for any lapses on set pieces.

“I guess that could be a possibility, but it's not an excuse,” Besler said. “That's the thing. It's not one guy. It's the whole team. Whoever's out there at the beginning of the game, at the end of the game – whoever's out there, every single person on the field – we need to be tuned in, and we need to be helping out each other. And right now at the end of the game, we're not locked in like we should be.”

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Goalkeeper Eric Kronberg, who was in goal when both potential clean sheets slipped away in the waning moments, echoed Besler's sentiments.

“We've got to have the team mentality to close the games out and be focused for 95 minutes, or whatever it's going to take to get the result we need,” said Kronberg, a longtime understudy who took over as Sporting's No. 1 with the retirement of Jimmy Nielsen. “We have the mentality. Maybe we lost it for a second, but we can't keep doing that. We've got to lock it down the last five minutes.”

Steve Brisendine covers Sporting Kansas City for MLSsoccer.com.