Frank Lampard has identified Liverpool as a significant threat to Chelsea's hopes of regaining the title before the teams' meeting at Stamford Bridge on Sunday. With both sides locked on 20 points at the top of the Barclays Premier League table, a stern examination is beckoning for the West London club, although as Lampard put it, he and his team-mates are already proving that they “mean business”.

Chelsea host Roma in the Champions League tomorrow evening before turning their attention to domestic matters. Luiz Felipe Scolari's players have kept five clean sheets in succession, scoring 13 goals in the process, including five aweay to Middlesbrough last weekend. The omens are positive, especially since Chelsea were without Petr Cech, Ashley Cole, Michael Essien, Ricardo Carvalho, Joe Cole, Didier Drogba and Michael Ballack through injury at the Riverside Stadium. “Everyone knows we mean business,” Lampard said. “Performances and results like Middlesbrough will show that.

“But everyone means business. Liverpool are getting results week in, week out like they have not done in the past few years, so they will be a threat. Manchester United are coming strong and Arsenal play great football. Everyone is trying to send out messages, but we are at the top and just want to stay there.”

While Gareth Southgate's side were poor on Saturday, the workrate of Chelsea's stand-ins was remarkable. “We believe in everyone,” Lampard said. “We would be quite happy with the same team against Roma. If we play with the same attitude, I think we have the quality in the team. The only way we can fail is when we do not work as hard as the other team.”

The sense of unity is a formidable strength. “It is testament to the squad that players like Juliano Belletti, who was fantastic at Boro, can come into the team,” he said. “There are big names and big players who are injured, but our squad keeps going.”