English FA Premiership/Arsenal v Chelsea: Tomorrow's top-of-the-table meeting at Highbury promises to be explosive if the managers' pre-match sniping is anything to go by. Arsenal's Arsene Wenger and Chelsea's Jose Mourinho traded blows from their respective training grounds yesterday ahead of the potentially decisive clash.

A suggestion by Wenger in his most recent programme notes that Arsenal have "30 times less investment capacity" than Chelsea proved the catalyst. It drew the pair into a testy long-distance debate, with Mourinho reacting angrily to the claim and Wenger biting back.

"They go season after season getting players like (Thierry) Henry, (Patrick) Vieira and (Jose Antonio) Reyes," said Mourinho "When Thierry Henry signed for Arsenal, was he free? Or when Patrick Vieira came here, was it on loan? It's a big surprise to me if Seville gave Reyes for free as a Christmas gift. Reyes, last Christmas, was quite an expensive gift."

He insisted his own outlay at Chelsea had been exaggerated and that analysing the teams' spending power head to head was unfair. "It is comparing a team that is seven-years-old against a seven-months-old team," he insisted.

Wenger did not mention Reyes, who cost an initial £10.5 million, in his response. He maintained he had never intended to offend Chelsea and was pointing to financial imbalance rather than pleading poverty but felt obliged to react to Mourinho's comments.

"He speaks about Vieira whom we bought for $5 million at that time," said Wenger. "You cannot say that's a big investment."

The Frenchman returned to the theme with his final words, adding: "Incidentally, we bought Henry with the money we generated from (selling Nicolas) Anelka. Less than half (of it)."

Wenger seemed equally unimpressed at a reminder from Mourinho that, regardless of tomorrow's outcome, Chelsea supporters will have the pleasure of chanting that they are top of the league. "That beautiful song our supporters sing, they can sing again," said Mourinho.

Wenger pointed out that the visiting fans would hardly be happy if Chelsea had lost, even though they would remain two points ahead. "We play at home, we just want to win," he said. "I don't think that you have fans who laugh when they lose their game."

Defeat cannot be contemplated by Arsenal, who would fall eight points adrift - a margin Mourinho called "significant". The Chelsea manager, who ruled out a January move for Liverpool's Steven Gerrard if his squad were injury-free but said the summer was too far ahead to consider, was happy to suggest that all the pressure was on Arsenal.

He said: "I always think pressure is on people chasing. It's better to be in front. You can make a mistake and still be in front. If you are chasing and make a mistake, it's more difficult. I don't want my team to be crazy with happiness if we win and I don't want them to be crying if we lose."

Was Wenger scared? "Very," said the Arsenal manager with heavy sarcasm. "It's terrible. It's the first big game of my career and I'm absolutely shattered."

More seriously he added: "We are ready and we have the talent and the spirit and we believe we can do it."

Yet Wenger's confident and occasionally jovial tone could not hide an unusual tetchiness when he was asked whether he admired the way Chelsea play and what Mourinho has been doing.

He said: "I am here to speak about Arsenal playing against Chelsea, not to speak about Chelsea playing against Arsenal. I am open to any question about Arsenal but I don't know why I should promote Chelsea before a game like this."

Mourinho had spoken admiringly of Wenger, saying: "He is one of the best in the world. If you're a foreign manager and stay here for a long period, you have to be really good or they kick you out."

Wenger remains confident of retaining the title. He believes his squad will peak near the end of the season and will benefit from knowing what it takes to win the Premiership. "We know how to win championships," he said while acknowledging that tomorrow will be important in the final reckoning. "I feel for us it's (important) to be as close to Chelsea as possible, to beat them on Sunday," he said.

"We have a young squad and I think in March, the time goes for us. In March we will be better than in December and in April we will be better than in March because every day these young players become better. I'm convinced we have great quality."

Wenger refused to confirm whether he would reinstate Jens Lehmann tomorrow, as expected, or keep faith in Manuel Almunia. "(Freddie) Ljungberg will play in goal," he said with a smile.

Let battle commence.