Chelsea manager Andre Villas-Boas has declined to blame Fernando Torres for his side's latest setback. The Spain forward, a £50 million signing from Liverpool a year ago, failed to add to his tally of just two Premier League goals this season. Chelsea were held to a goal-less draw at Norwich City in the Saturday lunchtime game but had created enough chances to have won. The clearest fell to Torres midway through the second half but he could only stab wide with the goal at his mercy. The result meant Chelsea had failed to put pressure on the three clubs above them, Manchester City, Manchester United and Tottenham, who all play on Sunday. It also left them vulnerable to a challenge for the fourth Champions League qualification spot by Arsenal, Newcastle and Liverpool in the coming weeks. Television footage had shown a frustrated Villas-Boas reacting angrily to the Torres miss, which was at least not as bad as the open goal he failed to find at Manchester United in September. Yet afterwards the former Porto manager was calmer and insisted he was satisfied with Torres performance. "He worked really hard, we were happy with his play," he said. "We can't be hypocrites and not take into account what he did in the last game, against Sunderland when everybody praised him. "He couldn't find the back of the net but we are not just looking for that. He had a good couple of chances, and for you to have chances you have to position yourself to have those good chances and he was there present. With a little bit more luck he will find the back of the net. "We created enough opportunities to win the game, not only for our striker but for our midfielders coming through. I think we are in the top three for teams creating goal-scoring chances. It's just finding that efficiency. It's been happening all season." There was more bad news as England midfielder Frank Lampard suffered a calf injury and had to be substituted in the 35th minute. "It looks like a muscle tear, we need to do an MRI to assess the full extent of the damage but from what I've been told by the doctors it doesn't look that bad," Villas-Boas added. Juan Mata hit a post late on and Norwich goalkeeper John Ruddy was kept busy throughout the 90 minutes as Norwich recorded their first clean sheet of the season. The Canaries were deserving of a point however with forwards Steve Morison and Grant Holt both coming close to scoring early on and the result further enhanced the growing reputation of Norwich manager Paul Lambert, who steered the club to successive promotions in his first two seasons. "John Ruddy was excellent but it wasn't just him," Lambert said. "I thought the whole group from the lads up front, to the midfield and the back four put their bodies on the line when they had to. "It was a huge point for us. Two years ago we were playing Yeovil, Walsall and Stockport and now we are playing against Chelsea, who are used to being in the Champions League, and competing with them. "I thought first half we were excellent. Second half, Chelsea had a lot of the ball which they are entitled to do as I think they are a fabulous side. You make no apologies for defending as strongly as we did in that half but in the first half I felt we gave as good as we got."