England are in a "fantastic position" to claim victory in the first Test against South Africa, says Steven Finn.
The fast bowler said England "back themselves" to take the six wickets needed to clinch the win on day five.
South Africa closed on 136-4, chasing 416, with AB de Villiers not out on 37.
"We can't complain about the position we are in, but we're going to have to be patient tomorrow," said Finn, who has taken 3-27 in the Proteas' second innings in Durban.
The 26-year-old, who was recalled to the side in July after a two-year absence, claimed the wickets of South Africa captain Hashim Amla, first-innings centurion Dean Elgar and, just before the close, Faf du Plessis.
"It's nice to be contributing when you come back into the team," he added. "I felt good and felt I was threatening. I ran in as hard as I could and luckily got a bit of extra bounce."
'De Villiers would have been a big wicket'
England could have been in an even better position if Jonny Bairstow had not missed a stumping chance offered by De Villiers off the bowling of Moeen Ali.
"It would have been nice to see the back of De Villiers but the ball span sharply and everyone backs Jonny to get the next one for us," Finn said.
"To see the back of him would have been a big wicket but to get the wicket of Du Plessis at the end definitely put a gloss on the day."
Former England wicketkeeper Matt Prior also defended Bairstow, calling it a "tough stumping chance" on Twitter.
But ex-England batsman Geoffrey Boycott told BBC Test Match Special the chance should have been taken.
"You have to take those chances," he said. "It was difficult, but it would have a capped a perfect day for England because De Villiers is the big fish of the whole game. He's a fantastic player, number one in the world for me, and if you get him out, the rest of them aren't special."
'South Africa must fight'
Former South Africa captain Graeme Smith told TMS it was vital for the Proteas to avoid defeat.
"South Africa have to fight and get something out of this Test match," he said. "I felt it was important for them to get off to a good start to get some self-belief with the quick turnaround between matches.
"It's so important for South Africa to get some good vibes out of this. The next day is so crucial for them."
South Africa spinner Dane Piedt, who took 5-153 in England's second innings, acknowledged the hosts faced a tough battle to save the game.
"We're really going to knuckle down and take it as long as possible," he said.