St Kilda coach Ross Lyon says he didn't see his side's second-half fadeout coming in its 19-point loss to Carlton at Marvel Stadium on Sunday.

Lyon said the Saints' midfield got "obliterated" by the Blues' onball brigade after half-time, meaning they struggled for territory, losing second-half inside 50s 31-19 and scoring only one goal after the main interval.

"After half-time they obliterated us, which is really disappointing because nothing really changed," he said.

"They just dominated and it just lived in our back half. Our midfield, which has been pretty good all year, just couldn't touch the ball. They didn't lay a glove on it. That division and that aspect of the game didn't deliver. It's been Carlton's strength and they did it.

"We've identified it. We'll review it. There's no recriminations. Sometimes you just get beaten but it's hard to swallow because I didn't see it exactly coming. Second halves have been our strength."

In its final three games with its top-eight aspirations on the line, St Kilda hosts Richmond and Geelong at Marvel Stadium, before a tough assignment away to Brisbane in round 24.

"It's not always about the ladder," Lyon said. "It's just about improving your footy and feeling good about yourself.

"If you play good footy, the wins come. We need to be better… our group has been very honest. There was no ranting or raving. They'll be hurting. It's a narrow window of improvement. But we're alive. We get another opportunity to deliver next week."