French League champions Lyon took the lead in a close, competitive match and looked on course for a shock win before Tevez intervened with just three minutes to go.
Both sides matched formations, forcing United's Tevez and Lyon's Hatem Benarfa onto the bench as each manager went with one striker flanked by two wingers.
The congested midfield played its role in a tight, though not unattractive, first half.
Lyon had the first set of chances, largely created by Juninho's masterful taking of free-kicks and corners, though only a Rio Ferdinand mis-kick came close to beating Edwin Van der Sar.
United had to wait 25 minutes for their first real chance - a long ball finding Wayne Rooney who flicked the ball past one defender and raced down on Gregory Coupet but the Lyon keeper parried and cleared his effort.
Spells of pressure from both sides failed to create many more opportunities, forcing United to come out after half-time with a more aggressive attitude.
Despite their intent it was a moment of brilliance from 20-year-old French sensation Karim Benzema that broke the deadlock after 54 minutes.
The striker received the ball just outside the box, spun past the four United defenders around him and drove in a stunning low shot which beat Van der Sar at his near post.
Suddenly United's plan to control possession and wait for a chance was ditched as the Premiership champions threw more men forward and brought on Nani and Tevez 65 minutes in.
Still Lyon held solid, with a disallowed Rooney goal - correctly ruled offside - and an excellent Cristiano Ronaldo free-kick, well saved by Coupet, being the sum total of United's attacking play.
Yet, in the 87th minute, following a saved Ronaldo effort, Nani's cross from the right was knocked from the back post to the front and Tevez was there to fire home from two yards out.
Lyon's resilience and work-rate deserved some reward but United will feel that their general dominance earned them the draw that they will happily take back to Old Trafford for the second leg in a fortnight's time.