Smith was relieved to earn a passage to the sixth-round

There were heated exchanges between Smith and Hibs boss Mixu Paatelainen after Nacho Novo was sent off for a reckless tackle on Thierry Gathuessi.

"I was upset at Hibs' reaction - the referee should be allowed to deal with the game," Smith told BBC Sport.

"But these things happen and I didn't think I'd get so excitable these days."

Interview: Rangers manager Walter Smith

The Ibrox side had Chris Burke to thank after his superb 39th-minute strike was sufficient to see off the challenge of the Edinburgh outfit, who still look for their first success in the competition since 1902.

"We made six changes today and it does take a team a while to settle," Smith added.

"I was a bit disappointed that we didn't build on our lead but I felt we deserved to go through overall."

Light Blues winger Burke, meanwhile, feels that Rangers' confidence is soaring as their season gears up with challenges for four trophies.

"I was happy with my contribution today - Hibs are a quality side and there's was always a danger they could equalise, but our defence was really tight," he said.

"Obviously our main priority is the title this season, but it's great to have so much to aim for and we all have a winning mentality in the team."