Jose Mourinho's side, who have plundered nine goals in back-to-back Premiership victories over Liverpool and Bolton, were simply irresistible as they took their tally to seven points from their opening three games.

Michael Essien, who was criticised for his tackle on Bolton's Tal Ben Haim at the weekend, responded with an inspirational performance in the Blues' midfield, laying on the opener for Didier Drogba and teeing up the impressive Joe Cole for the third.

Ricardo Carvalho and substitute Hernan Crespo were also on target for the home side who were rarely threatened after resisting an early assault from Betis.

Spain international Joaquin, reportedly a transfer target for Chelsea in the past, was the architect of a flurry of early chances for the visitors as they made good on their promise to take the game to the Premiership champions.

In the third minute, Joaquin's well-struck free-kick was deflected narrowly wide by Frank Lampard and from the resulting corner, also delivered by Joaquin, Juanito's header was cleared off the line by Claude Makelele.

Juanito then met another Joaquin cross with a flicked header at the near post but the ball struck his team-mate Ricardo Oliveira on its way to goal.

However, once Chelsea had weathered the early storm it was one-way traffic in their favour.

Cole, who had been showing off his dazzling array of skills in the early stages, flashed in a low drive which Antonio Doblas did well to kick to safety, before Drogba fired a warning with a shot which went wide from 20 yards.

Drogba should have opened the scoring when he was picked out by Shaun Wright-Phillips, but he could not direct his six-yard volley on target.

Six minutes later, though, the Chelsea striker made the breakthrough after some magical work by Essien, who dummied to pass to Wright-Phillips on his right before angling a low ball to his left to Drogba, who beat Doblas for his eighth goal of the season.

Chelsea were then gifted a second moments before the interval when Lampard's harmless-looking free-kick was spilled on the goal-line by Doblas and Carvalho was able to turn the ball in from two yards.

That second goal effectively killed off the contest, yet Chelsea looked hungry for more goals at the start of the second half and they duly added a third just before the hour mark.

Essien was the inspiration once again, driving forward from midfield and releasing Cole, who advanced to the edge of the penalty area before curling a shot around Doblas and into his bottom left-hand corner.

Drogba had picked up a slight knock in the first half and was withdrawn at the interval to be replaced by Crespo, and it was the Argentine striker who rounded off the scoring with the pick of the goals.

Lampard's driven 40-yard pass sent Wright-Phillips away down the right flank and the England winger's first-time cross was headed in powerfully by Crespo.

Betis might have had a consolation had referee Terje Hauge seen Asier del Horno's trip on Joaquin in the penalty area, but instead the Norwegian official booked the Betis man for diving.