Chelsea’s Champions League soccer hopes are in the balance following a 3-1 loss to Napoli in the first leg of their last-16 tie on Tuesday, after Real Madrid were pegged back by a 93rd-minute equaliser at CSKA Moscow.

The Londoners took the lead through Juan Mata at Napoli’s Stadio San Paolo but a brace from Ezequiel Lavezzi and another goal from Edinson Cavani turned the tie in the Italian side’s favour ahead of the second leg on March 14.

Coupled with Arsenal’s 4-0 loss at AC Milan and early exits for Manchester United and Manchester City, Chelsea’s defeat raises the prospect of the quarter-finals being devoid of English teams for the first time since 1996.

“We should have defended better. A couple of mistakes against Napoli and you’re going to get punished,” said Chelsea coach Andre Villas-Boas.

“… 3-1 is more difficult to recover but not impossible with the amount of chances we get. The first 90 minutes have passed but we have 90 minutes to go to turn the tie around.”

Villas-Boas started with Ashley Cole, Frank Lampard and Michael Essien on the bench and his side quickly found themselves on the back foot, with Petr Cech saving sharply from Cavani and Christian Maggio early on.

It was the visitors who struck first, however, as Mata capitalised on Paolo Cannavaro’s miscued clearance to place a cool volley past Morgan De Sanctis in the 27th minute.

Chelsea could not hold out until halftime, though, and two quick-fire goals put Napoli ahead.

Lavezzi equalised in the 38th minute by bending a low shot around Cech from the edge of the box and, in first-half injury time, Cavani stole in front of Branislav Ivanovic to divert Gokhan Inler’s cross into the roof of the net with his shoulder.

Lavezzi dragged wide when well placed in the 55th minute but he made amends 10 minutes later, tucking the ball into an unguarded goal after Cavani had blocked David Luiz’s weak attempted clearance.

Real Madrid remain favourites to reach the quarter-finals despite Swedish debutant Pontus Wernbloom rescuing a 1-1 draw for CSKA with an injury-time equaliser after Christiano Ronaldo’s opener at a sub-zero Luzhniki Stadium.

Wernbloom, making his CSKA debut after signing from AZ Alkmaar in January, struck with the last kick of the match to prevent the Spanish champions-elect recording their seventh straight win in the competition.

“It’s a good result for us in the away leg,” said Madrid coach Jose Mourinho.