Arsenal boss Arsene Wenger admits his side must be on their guard when they come up against Tottenham Hotspur striker Dimitar Berbatov.
Top of the table Arsenal host their fierce rivals at lunchtime on Saturday, live on Sky Sports 1, and The Gunners manager is wary of Berbatov's quality.
"It seems, especially in the last two or three games, that when Berbatov plays well, so do Tottenham," Wenger said.
"The quality of Tottenham's performances recently can be linked with the gain in form of Berbatov.
"His intelligence, his technique and the quality of his movement have impressed me. He is one of the Premier League's better strikers."
Wenger went on to back Spurs boss Juande Ramos - who he believes will bring success to White Hart Lane.
"I think Ramos can achieve something at Tottenham. He has the experience and plenty of resources," he continued.
"He has the chance to do it because Tottenham already had a good team before he came - they have finished fifth for the last two seasons."
The Gunners manager also defended full-back Emmanuel Eboue after his challenge on John Terry last Sunday broke the Chelsea captain's foot.
"I watched Eboue's tackle again and I don't think he wanted to 'do' John Terry," he said.
"He touched him and I'm really sorry that John was injured. Ideally, Eboue shouldn't have put his foot in there. We do not encourage our players to do that.
"But John Terry should not have been on the pitch at that time because his tackle on (Cesc) Fabregas was the worst of the match.
"I think he would have been sent off had he not been England captain. If you start to think like that you become mad.
"But the referee did not see exactly the violence of the tackle. Terry got away with it and good luck to him.
"But that didn't mean we wanted to injure him. I want my players to behave well and we do not want to injure people."