Chelsea missed the chance to take over the Premier League leadership when held to a draw at the Riverside Stadium.
Chelsea have proved a bogey team to Middlesbrough over the years but on this occasion they had to be content with a point.
Middlesbrough manager Steve McClaren had dismissed the idea that this was a dress rehearsal for the FA Cup tie in early January.
Middlesbrough went ahead with a brilliant free-kick by midfielder Geremi who is on loan from Real Madrid. The Cameroonian curled a 25-yard shot into the roof of the net to leave Carlo Cudicini helpless.
Shortly after Middlesbrough had a great chance to increase the lead when Szilard Nemeth broke through on the right.
Nemeth provided a perfect chance for Massimo Maccarone, but the Italian, with time and space, shot past the far post.
Chelsea made the most of this escape by snatching an equaliser three minutes before the interval. Boro failed to clear the corner and John Terry scored in a crowded penalty area.
With Maccarone lacking confidence it was no surprise when he was replaced in the second half by Noel Whelan.
Jimmy Hasselbaink was ineffective in the Chelsea attack, but Mark Schwarzer was the busier goalkeeper.
Chelsea manager Claudio Ranieri said: "I thought we deserved to win. We had more chances than Middlesbrough but we had an off day in front of goal.
"I did not think it was a free-kick that led to MiddlesbroughÂ’s goal but the home side played much better in the second half. It was a very open game." Middlesbrough manager McClaren summed up: "It was important not to lose and important to maintain our unbeaten run at home. No team will have an easy game here.
"Chelsea are more resilient than last season and I think they are genuine title contenders." McClaren praised his players for their commitment and claimed Nemeth had scored a perfectly good goal that was disallowed for offside.
"I brought Maccarone off at half time for tactical reasons. He has not missed a game this season at some stage he will need a rest," McClaren concluded.