World champion Ricky Burns believes he can continue to improve after adding another dimension to his game with a stunning fourth-round stoppage of Kevin Mitchell.

The consensus in the boxing world was that the WBO lightweight title fight in Glasgow could go either way with Burns' staying power and tactical nous in contrast with Mitchell's punching power. But Burns confounded expectations by going on the front foot early on and putting Mitchell under sustained pressure and that pressure told in the fourth with Mitchell on the canvas twice before referee Terry O'Connor stopped the contest amid a barrage of punches.

After thrilling a capacity crowd at the SECC with his seventh world title fight victory, Burns said: "The first round I was just trying to suss him out but I knew myself once I upped the pressure, I was just trying to smash them in. I have been feeling so much physically stronger and I think it showed. And I think there is more to come."

Burns was fighting only his third contest since stepping up to lightweight but looked bigger, stronger and faster than Mitchell, who suffered the second defeat of his career.

The 29-year-old Scot once again saved his best for the big occasion, as he had done when winning his first world title against the otherwise unbeaten Roman Martinez, and when he outfought and out-thought Michael Katsidis to win his current belt.

Burns has been seeking a unification fight or a challenge for a Ring magazine title since his super-featherweight days but he will allow promoter Frank Warren the ultimate choice in his next defence. Former world featherweight champion Scott Harrison, who won his second comeback fight on points on Saturday night, is a possible opponent but perhaps not this year.

Burns said: "I'm off to Vegas next week on holiday but my training stuff will be coming with me.

"Frank says I will be out on December 8 or 15 so I'll have a couple of weeks off and then get back in the gym.

"I'll fight whoever is put in front of me. They know the fights I want, I'd love to go after the Ring magazine and try to unify but I'll just take it a fight at a time.

"I know Scott is itching to get a world title fight. Obviously in Scotland it would be a massive fight. But we'll find out in a few weeks."