The 28-year-old, who had earlier given his side the lead, limped off the pitch an hour into the Magpies' 3-3 Barclays Premier League draw with Burnley at St James' Park on Thursday afternoon and acting manager John Carver later revealed the club's medics are fearing the worst.
Carver said: "Unfortunately, we have lost Steven Taylor. It looks like he has ruptured his Achilles tendon - and it's not the one he did previously, so I think that's the end of him now for the season.
"I have known Steven since he was in the Centre of Excellence and he is a great lad. It was great for him to get the goal at a set-play, it was set up for him.
"But when he landed, you could tell the way he landed it was something to do with the calf or Achilles and unfortunately it's not looking good."
It proved a day for injuries on Tyneside as Burnley lost three men before half-time with Jason Shackell and Dean Marney leaving the field under their own steam and Kevin Long, who was making his league debut as a 17th-minute