After more displays like this from Foster, the grin will soon be disappearing from Hart's face.
Of course, Hart resurrected his career at St Andrew's and now Foster is following in his footsteps. And then some, judging by his display in Saturday's 1-0 win over Chelsea.
Gloving it: Ben Foster denies Drogba and Chelsea again
It was one of those days - as the former trainee chef admitted afterwards - when everything turned out as he wanted.
The pick of Foster's saves was from Didier Drogba's first-half header, lauded afterwards as 'Gordon Banks-esque' by Birmingham boss Alex McLeish.
FOSTER'S SUPER SAVES Minute Saved from4Ramires6Drogba22Drogba24Drogba29Cole31Anelka37Drogba71Drogba76Ivanovic
Foster just seemed to enjoy the match. He parried, saved and even tackled his way to a clean sheet, alongside similarly heroic showings from home centre halves Roger Johnson and Scott Dann, that made any criticism of the keeper after Karim Benzema's opening goal at Wembley onWednesday a distant memory.
McLeish has already claimed the Foster versus Hart conundrum could dominate English goalkeeping for years to come. His assessment suggests Fabio Capello may be in for a difficult choice.
'Joe had a couple of wee rough edges when he came,' said the Birmingham manager. 'Ben doesn't have those. It may be because he's more experienced. He's played every week in the Premier League before and been at Manchester United.
'Sir Alex (Ferguson) told me he would be in the England team before the end of this year when he signed.
Singing the Blues: The Birmingham keeper celebrates victory with Liam Ridgewell
'Today, he really did show what he could do.'
Foster admitted he was in the zone. However, there was also some encouragement for Chelsea when he said he had never been put under as much pressure as he was by Drogba and his team-mates after the break.
Birmingham enjoyed just one shot, with Chelsea having 25 in total. It was a fair reflection of the away side's dominance and also reflects the sheer brilliance of Foster and his team in repelling wave after wave of attacks. 'I did have that kind of feeling that I was in the zone,' said the keeper.
'I just thought that anything they put into the box I was going to get. I was going to punch it, or collect or save.
'It was unbelievable to get a clean sheet with the pressure they had.
'These boys in front of me, they are proper defenders. They just love defending. There's no fancy-dans here.
'Ask them to head it and away it goes. Ask them to put in a crunching tackle and in it comes.
EUROWATCH Tomas Oravec's goal wasn't enough for Slovakia league leadersMSK Zilina as they slumped to a 2-1defeat at second-placed FK Senica.They played on Friday, though, so have one day more to prepare than Chelsea.
'But I've not played in anything like that. It was a major backs-to-the-wall job. The second half especially was an onslaught.
'We realised the situation. They knew the score. They were attacking, we were defending, it was as simple as that. We just managed to keep them out.
'There didn't seem too much wrong with Chelsea from where I was.These results don't happen too of ten. Look at the statistics.'
As for Hart, Foster said: 'He came into our dressing room after the game last week and was laughing about the chant from our supporters.'
You suspect Manchester City's keeper may not be as happy this week.
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