Luis Suarez opened the scoring just after the hour mark before Gerald Sibon pulled Heerenveen level 10 minutes later.

But John Heitinga pounced in the 76th minute to leave Ajax on the brink of qualifying for the play-off final.

Ajax, who ended Heerenveen's European dream last year with a 4-2 aggregate win, will hope to complete the job in the second leg at the Amsterdam ArenA on Monday.

The first decent effort of the match came in the 22nd minute when Suarez latched onto Dennis Rommedahl's through-ball only to see his 15-yard shot tipped over the bar.

Kenneth Perez was unlucky not to fire Ajax in front on the half-hour mark when his 30-yard thunderbolt flashed just wide of the right post.

Sibon should have given the hosts the lead minutes before half-time but Ajax goalkeeper Maarten Stekelenburg pulled off a great save to keep out his 12-yard shot.

The second half was a much more entertaining affair and the deadlock was finally broken in the 61st minute.

Suarez broke through the Heerenveen defence to find himself one-on-one with the goalkeeper, and he gave Rob van Dijk no chance as he lashed home from 10 yards.

The hosts were level after 71 minutes as Sibon headed in the equaliser from close range following a good cross from Roy Beerens.

But Ajax were back in front and in control of the tie just five minutes later, with Heitinga rising highest in the area to head home Bruno Silva's cross.