MARTIN Petrov believes Tottenham and Arsenal missed out on the best centre-back in the business when they failed to sign Gary Cahill in the transfer window.

The Bulgaria international prepares to go head-to-head with his Wanderers team-mate in Sofia tonight.

But just 48 hours ago, Cahill was at the centre of a £13million tug of war between Harry Redknapp and Owen Coyle, which ended with the England star staying put at the Reebok against the odds.

Arsene Wenger had also tested the water last week with a paltry £7million offer - but with Wanderers digging in their heels to keep the 25-year-old, Petrov believes they have pulled off a masterstroke.

“For me, he is the best defender in the whole league,” said the winger, who will be winning his 89th cap for his country at the Vasil Levski Stadium.

“He is strong, quick and can head the ball well. For me, they would have to pick him.

“Am I surprised he is still at Bolton Wanderers? That is not a question for me.

“For the team it is very good that he would stay here. But if the club choose to sell, I think we must understand that he is a very good player who wants to go forward in his career.”

Cahill has become a regular squad member under Fabio Capello but still has only three caps to his name, including just one start in a friendly against Ghana.

He is up against Joleon Lescott, Chris Smalling and Phil Jones for a place alongside John Terry - and Petrov believes the number of available options for the England boss in defence have stunted his friend’s international chances.

“England have so many quality players,” he said. “Probably too many.

“In my country we do not really have that problem. It is quite easy to pick the squad. But in England there are so many good defenders, it has taken time for them to see how good Gary is.”

Cahill made his debut as a substitute for the injured Michael Dawson in a 4-0 victory over Bulgaria last September at Wembley but Petrov has warned England to expect a sterner test this time around as his country look to prolong their slim chances of qualification for next summer’s tournament in Poland and Ukraine.

“The stadium will be full and it will be a big atmosphere,” he told The Bolton News.

“Okay, we know we might not have a great chance of beating England, but this is football. We must play like one team and if we can do that, I think we stand a chance to take something.

“We are very different teams. England players all play in the Premier League, probably the best league in the world.

“But I think it will be difficult because we are at home and the fans will be there for us.

“I think it will be a great game but I hope that Bulgaria win.”