The tepid 0-0 draw in the Vicente Calderon resembled a phoney war but Chelsea and Atletico Madrid will surely up the ante at Stamford Bridge on Wednesday when a place in the Champions League final is on the line.

That semifinal first leg stalemate left Chelsea marginal favourites to progress although with no away goal in their pocket, Jose Mourinho’s side will be vulnerable against an Atletico side capable of much more than they produced at home.

Atletico, closing in on a first Spanish league title since 1996, ran out of ideas against a resolute Chelsea rearguard in which John Terry and Gary Cahill spent most of the evening heading away hopeful crosses into the area.

The Londoners are sweating on the fitness of Terry, who turned his ankle in the first leg and they will be without injured goalkeeper Petr Cech and suspended midfielders Frank Lampard and John Obi Mikel.

Whoever plays, Atletico coach Diego Simeone needs a different game plan if his club are to reach the final for the first time since 1974.

They enjoyed 64 percent of the ball last week but leading striker Diego Costa barely got a sniff of a chance as the two sides effectively cancelled each other out.

Simeone's side, who have conceded the fewest goals in La Liga this season, have won their last nine Spanish top-flight games and are on a 14-match unbeaten run in all competitions.

With a relatively thin squad he was unable to rest any of his regulars in the 1-0 win at Valencia at the weekend, although Gabi played down talk of heavy legs as the season reaches its climax.

“We are up on a cloud from which we don't want to get down,” Gabi, who will miss the second leg through suspension, told reporters. “The team has a level of conviction that has rarely been seen.”

Simeone, however, issued a word of caution. “La Liga is nothing like the Champions League,” he said before referencing a weakened Chelsea's 2-0 win at Premier League leaders Liverpool at the weekend.

“Chelsea has a great team, the possibility of rotating and winning 0-2. We face a very powerful team that will make it very hard for us.”

Mourinho is a past master at knocking teams off clouds and while Simeone will demand more imagination from his side at Stamford Bridge where an away goal could prove vital, Mourinho may elect to adopt the tactics that so stifled Atletico and Liverpool in the space of a few days.

The onus is on Chelsea to score a goal this time but Mourinho is unlikely to become all gung-ho even if the creative talents of Eden Hazard and the scoring prowess of Samuel Eto'o are at his disposal after they missed the first leg injured.

Former Porto and Inter Milan boss Mourinho is attempting to reach his third Champions League final with a third club, having fallen in three consecutive semifinals while in charge of Real Madrid.

He also lost semifinals with Chelsea in 2005 and 2007 during his first spell in charge so no wonder he appears to have demoted his side’s Premier League challenge below that of winning the Champions League.

The omens look good for Chelsea too.

They are unbeaten in their last 16 clashes with Spanish sides in the Champions League, winning six and drawing 10 since losing to Barcelona in February 2006.

Atletico’s only victory in nine European ties on English soil came at Leicester City in 1997 although they have proved formidable foes in this year’s Champions League and reached the semi-finals unbeaten.

Chelsea skipper Terry, suspended for his side's Champions League triumph in Munich in 2012, will be assessed on Tuesday to see if he can lead his side to a third final.

“He has a chance for Wednesday's game,” Mourinho said. Like Terry's fitness, the tightest of ties also hangs in the balance.