Terry was making his return after a four-game domestic ban for racially abusing Queens Park Rangers defender Anton Ferdinand last season, and he broke the deadlock against Liverpool with a 20th-minute header.
However, 19 minutes later he left the fray on a stretcher, his head in his hands, following a collision with Luis Suarez, who added insult to injury by scoring the visitors' equaliser with 17 minutes to play.
The result left the European champions three points behind leaders Manchester United and one point below City, who came from behind to win 2-1 at home to Spurs thanks to an 88th-minute winner from substitute Edin Dzeko.
At Stamford Bridge, Terry glanced home Juan Mata's corner to break the deadlock and claim his 50th goal in Chelsea's colours, but the former England defender did not make it to half-time.
His right knee buckled after Suarez fell on top of him, prompting an anguished cry that was picked up by television microphones and necessitating five minutes of treatment before he was carried off by medics.
Chelsea came close to extending their lead on several occasions, most notably when Mata fired over late in the first half and when Liverpool goalkeeper Brad Jones produced a reflex save to block Fernando Torres' second-half header.
Suarez had been having a quiet game but in the 73rd minute he popped up to claim the equaliser, nodding in from close range after Jamie Carragher flicked on Suso's corner to record his eighth league goal of the campaign.
It was Liverpool's third consecutive draw and left Brendan Rodgers' side in 13th place.
Dzeko's late strike gave City victory over Spurs at the Etihad Stadium, as Roberto Mancini's side emulated United's 3-2 win at Aston Villa on Saturday by coming from behind to win.
City trailed to Steven Caulker's 21st-minute opener but drew level through Sergio Aguero in the second half before Dzeko struck late on to close the gap on United to two points.
"It was a huge win because it was a difficult moment," said City coach Mancini.
"We had a lot of important players injured and today I saw the same spirit from the players that I saw last year.
"In the first half we played well. I didn't feel Tottenham had chances apart from a couple of set pieces. We need to improve there. But after they scored first, I thought we played fantastic."
The visitors successfully marshalled City's attacking players in the opening stages and went ahead in the 21st minute when Caulker met Tom Huddlestone's free-kick with a header that Joe Hart fumbled over the line.
Huddlestone came within inches of extending the visitors' lead with a crisp drive, but City felt they should have been awarded penalties for an apparent William Gallas handball and a block by Huddlestone on Pablo Zabaleta.
Carlos Tevez and Zabaleta both tested Spurs goalkeeper Brad Friedel in the minutes prior to half-time, before Aguero drew the hosts level in the 65th minute.
David Silva's pass was inadvertently diverted into Aguero's path by a Spurs player and the Argentine cut inside Caulker before rolling the ball past Friedel.
Silva shot wide and Friedel saved well from Aguero, but victory looked set to elude the home side until Silva picked out Dzeko with a chipped pass and the Bosnian hooked a left-foot half-volley into the roof of the net.
In the day's other game, Kevin Nolan returned to haunt former club Newcastle United by scoring the only goal of the game as West Ham United won 1-0 at St James' Park to climb into the top six. – Sapa-AFP