Pressure is mounting on Vaughan after another batting failure
Opener Alastair Cook jumped to Michael Vaughan's defence after the England captain again failed with the bat.
Vaughan was dismissed for a first-ball duck on day one of the third Test against South Africa and has scored just 24 runs in his last four innings.
But Cook said Vaughan's loss of form is temporary, insisting: "It was a tough day, but Vaughany always come out the other end, he's a quality player.
"The statistics suggest that and he will definitely come through."
Cook top-scored with a defiant 76 in England's first innings of 231, sharing a 69-run opening partnership with Andrew Strauss as well as a 62-run fourth-wicket stand with Ian Bell.
But the Essex left-hander admitted he was disappointed not to convert his promising start into his eighth Test century.
We have to fight our way back and bowl them out to put them under some pressure
England coach Peter Moores
"I have had a few 50s, 60s, 70s and not gone on," said Cook. "That's disappointing, but that might turn around if I don't think about it too much because it could become a mental barrier.
"We had good partnerships - but that's the difference between getting a really big score, turning those partnership into match-winning stands."
Andrew Flintoff's late dismissal of Graeme Smith will give England plenty of encouragement when South Africa resume their innings at 38-1 on Thursday.
And bowling conditions could suit England's swing bowlers, with weather forecasts indicating overcast conditions in Birmingham.
"Hopefully it will be cloudy and we can get that swing, which could play to our advantage," said Cook.
"If we can start well, with two or three wickets in the first hour with the ball swinging then we're right back in the game."
England coach Peter Moores also urged his side to haul themselves out of trouble on day two at Edgbaston.
"We have to pull ourselves tight, get out there and scrap hard to get ourselves back into the game," said Moores.
"We wanted to get more runs but we know what we've got, so we have got to come back with something.
"We have to fight our way back and bowl them out to put them under some pressure."
South Africa produced another impressive display in the field on the opening day, with Andre Nel taking three wickets on his Test recall.
The eccentric fast bowler took the vital wickets of Strauss - who trod on his stumps - and Cook just as England were building promising partnerships.
"At that stage of the game we needed that wicket (Strauss), it worked out nicely," said Nel.
"We didn't bowl as well as we should have before lunch. We had to be patient and there's always something for the bowlers here, the ball swings a bit more here."
Nel was quick to praise all-rounder Jacques Kallis, who also collected three wickets as well as a low catch at second slip to dismiss Cook.
"Jacques bowled an unbelievable spell into the wind, it was nice to bowl with him as he kept it so tight," said Nel, whose alter ego "Gunter" had earned him plenty of column inches before the Test.
"He was a bit tired as the old guy in the side! The ball swung for him today, he enjoyed it.
"It was a good day for us but tomorrow is a big day. We have to score runs on the board and bat as long as possible, get a nice lead and put them under pressure again."