MANY believed that the signing of Andriy Shevchenko would marginalise Didier Drogba at Stamford Bridge, but the reverse is happening. Despite Shevchenko’s pedigree, Drogba’s authority grows with each strident performance.

The forward’s first hat-trick for Chelsea, three pieces of opportunism, took his tally for the season to seven last night. Shevchenko has one. Despite Barcelona rescuing a point away to Werder Bremen, Chelsea have moved to the top of group A and will feel optimistic before the European champions’ trip to the capital on October 18.

Still, Levski Sofia were testing opponents and Chelsea’s defence never appeared secure, while Shevchenko seemed positively insecure despite his excellent record in Europe. This was his 100th appearance and he has 56 goals.

José Mourinho’s explanation that the forward spends a lot of time assisting the midfield was not valid here. Shevchenko lurked in and around the penalty area but looked gauche and even if the manager is not putting pressure on his £30 million signing, the Ukrainian’s body language suggested a degree of self-criticism.

Shevchenko, whose 30th birthday is on Friday, has not scored for six matches and has been substituted in each. Mourinho agreed that he needs a goal to augment his confidence and the striker will be given every opportunity to get it.

“Until he scores a goal he is in my line-up, no chance to be out,” the manager said. “Two, three, four, five [games] — he will play until he scores a goal.” Mourinho’s praise for Drogba was curiously low-key, perhaps because he wanted to avoid an implicit contrast with Shevchenko. “Three goals is always nice,” he said. “It’s a day to remember. Didier scoring goals or other players scoring goals — it is so not important for me.”

“The hat-trick meant a lot to me because I’ve been looking for it since I came here,” Drogba said. “OK, I’m very happy, but the most important thing in the Champions League is to win away.” It is not a feeling that Chelsea have enjoyed much in the past year. This was only their second win on the road in nine European games.

“We’re playing well enough but still not playing very, very well,” Mourinho said. “Cool, calm and solid — good enough. But we need to improve.” And greater fluency may not be imminent. Mourinho’s upper lip curled at the thought of the forthcoming international break.

Despite claiming before the match that he would pick his best side, Mourinho rested Claude Makelele and Ashley Cole. Wayne Bridge was excellent in Cole’s place and Michael Essien was a dynamic presence in the midfield holding role. Jon Obi Mikel, the teenager, made his first start and played with maturity except for one fit of pique after he was booked for feigning injury.

John Terry returned after missing last Saturday’s win over Fulham with back spasms. Michael Ballack, suspended in the Barclays Premiership, was also in the line-up again.

Levski, who were beaten 5-0 by Barcelona two weeks ago, are the first Bulgarians to reach the Champions League group stage and they borrowed the national Vassil Levski Stadium in central Sofia for the occasion. It was virtually full more than an hour before kick-off and the fans produced a formidable din.

Given the febrile mood and the turf made sodden by a day of incessant rain, it was no surprise that Chelsea began hesitantly. Despite Levski’s early threat, the Londoners should have taken the lead after 14 minutes when the ball broke to Drogba ten yards out. Unmarked, he crashed it off the underside of the bar. Six minutes later, a swerving effort from 25 yards by Ballack was pushed on to the post by Georgi Petkov.

Chelsea did score six minutes before half-time. Petkov saved well from Mikel, but Drogba connected this time and put away the rebound. Eight minutes into the second period he doubled the lead, capitalising on a defensive mistake that put him clean through. The ball slipped under Petkov’s dive and trickled into the net.

Surprisingly, Drogba’s celebrations seemed more muted when he completed his hat-trick — perhaps a reflection of the shambolic nature of the strike. Frank Lampard lashed a shot across goal and Drogba appeared to miscontrol it into the net from six yards.

It was, in fact, the cue for sustained Levski pressure that forced Petr Cech into some fine saves. He could do nothing about a fine finish from Maryan Ogbyanov two minutes before the end, but even if Mourinho was unhappy at the way his side went from Sofia to sofa after their third goal — and at the news of Barcelona’s late equaliser — this was still a satisfactory night, for most in Chelsea colours, anyway.

LEVSKI SOFIA (4-2-3-1): G Petkov — Z Milanov, E Topuzakov, I Tomasic, L Wagner — D Borimirov (sub:M Koprivarov, 79min), R Eromoigbe — D Telkiyski (sub: G Ivanov, 67min), C Bardon (sub: M Ognyanov, 71), S Angelov — H Yovov. Substitutes not used: N Mihaylov, B Hristov, V Minev, M Ivanov. Booked: Angelov.

CHELSEA (4-1-3-2): P Cech — P Ferreira, R Carvalho, J Terry, W Bridge — M Essien — J O Mikel (sub: S Kalou, 63), M Ballack, F Lampard — A Shevchenko (sub:S Wright-Phillips, 82), D Drogba (sub:A Robben, 70). Substitutes not used: Hilario, A Cole, C Makelele, K Boulahrouz. Booked: Obi Mikel.

Referee: L Duhamel (France).