Tony Rea was a relieved man after his London Broncos side avoided a Challenge Cup upset by defeating Featherstone 24-12 at the Stoop.
The hosts trailed 4-0 at the interval but rallied with five second-half tries to book their place in the fifth round.
Rea admitted his side would have crashed out had they not got their act together after the break.
He said: "We could easily have rolled over and lost the game in the first half as we were not playing well.
"But our defence was outstanding and that was hugely important to us.
"We showed the attitude and character to hang in there and turn it around, which really pleases me.
"We realised we had to earn the points if we were going to come out on top.
"All credit to Featherstone, though - they gave us exactly the type of contest I thought they would and they were a credit to the cup competition."
Kieran Dixon and Luke Dorn each grabbed second-half braces with Jamie O'Callaghan also bagging a try to secure a double-scores win.
Ian Hardman claimed two tries for the Rovers, who also had a second-half score from the influential Andy Kain to show for their prodigious efforts.
"It was definitely a missed opportunity from our point of view," said Featherstone coach Daryl Powell.
"I didn't think there was anything between the teams really, but we lacked that cutting edge that could have made the difference.
"We had them under a lot of pressure in the first half but we could not come up with the points."