Lyon had been largely on top at the Gerland stadium and Florent Malouda’s early goal looked to have given the Frenchmen the advantage before the second leg in the Netherlands on Wednesday next week.
However, 34-year-old former Barcelona midfielder Cocu changed all that with his late goal.
Running upfield, he played a one-two with South Korean Park Ji-Sung and, with the luck going Cocu’s way as the ball cannoned into his path, finished the move with an accurate left foot shot past Lyon keeper Gregory Coupet.
A disappointed Lyon coach Paul Le Guen told French television station TF1 afterwards: “It was not a good result tonight. We had much the better chances. But PSV have good technique, great ability and were able to take advantage to earn a draw.”
Lyon reached this stage with a 3-0 success away to Werder Bremen before winning 7-2 at the Stade Gerland and were boosted by the news that captain Claudio Cacapa was fit after suffering a serious knee injury.
The 28-year-old Brazilian defender proved his fitness after two reserve games and was ready to return after nearly five months out.
PSV coach Guus Hiddink fielded the same starting 11 which twice beat Monaco last month to book their last eight berth. They lead the Dutch league by 10 points having won 13 matches and drawn once since mid-December. Malouda scored the opener in the 12th minute. Sidney Govou, out on the right, passed into the area to Sylvain Wiltord in the middle of the area who was trying hard to control the ball among a crowd of players.
The ball then came out to Malouda at the far post and he tucked the ball neatly inside the right hand post of PSV keeper Heurelho Gomes.
Mahamadou Diarra had a chance with the outside of his right foot and Mickael Essien had a headed effort from the penalty spot caught by keeper Gomes.
In the 39th minute, PSV had a real scare when an Essien shot beat keeper Gomes, diving to his left, and hit the post.
However the Dutch team had an opportunity when Jan Vennegoor of Hesselink’s turn and shot sailed over Gregory Coupet’s crossbar.
Lyon went into the break with a deserved lead having been on top in virtually every department of the pitch with striker Wiltord in particular having a good game.
On the restart, a Juninho freekick was punched away by Gomes as Lyon kept up the pressure. A golden opportunity for Paul Le Guen’s men to go two goals up came in the 63rd minute however. Govou’s shot from inside the area was brilliantly deflected away for a corner by Gomes, diving to his left.
South Korean winger Park Ji-Sung, who was man-of-the-match when PSV beat Monaco last month, had been having a quiet game with Lyon defender Anthony Reveillere blunting Park’s forays on the left flank.
Then came Cocu’s 79th minute goal which spoiled the evening for most of the 39,178 crowd and gave Hiddink’s men the advantage with the final leg in The Netherlands.
: Coupet, Cris, Essien, Cacapa, Reveillere, Abidal, Diarra, Juninho, Malouda, Govou, Wiltord.
: Gomes, Ooijer, Lee, Alex, Bouma, Van Bommel, Park, Cocu, Vogel, Vennegoor of Hesselink, Farfan.
: Pierluigi Collina (Italy).