ALKMAAR, Feb 25 (SW) - A draw at AZ Alkmaar versus Ajax Amsterdam left PSV with increased chances of winning this year's Dutch championship.

PSV Eindhoven had won their home match with FC Groningen on Saturday, but it was anything but easy for the reigning champions. Ronald Koeman's side struggled to get through Groningen's defense but eventually earned three points as Brazilian defender Alex scored from a corner kick in the 87th minute.

This added pressure on Sunday's top clash between third-placed AZ and second-placed Ajax Amsterdam, a match in which referee Jan Wegereef would be of great influence.

Wegereef provided Ajax' Edgar Davids with two yellow cards in the first half, and particularly the first booking was questionable.

Despite the numeric disadvantage, it was Ajax to take the lead in the 65th minute though Danish midfielder and former AZ player Kenneth Perez.

But Wegereef again demanded all attention in the 79th minute. A Demy de Zeeuw challenge on Ajax goalkeeper Stekelenburg was left unpunished and allowed Maarten Martens to level the score. Frantic Ajax protests had no result.

At the post match press conference, Ajax manager Henk ten Cate stated that his team faced 'FC Wegereef' during the ninety minutes in Alkmaar.

Fourth-placed FC Twente, who hosted Willem II on Saturday, failed to score and do not take advantage of the result at AZ-Ajax on Sunday.

Feyenoord meanwhile had another bad day as Erwin Koeman's side were held to a 3-3 draw at last-placed ADO Den Haag.

The Rotterdam outfit took the lead twice, through Joonas Kolkka and Angelos Charisteas respectively, but allowed Rick Hoogendorp to equalize in both occasions. ADO's second goal came from the penalty spot.

The home side then even seemed to be heading for victory as Laurent Delorge scored for 3-2 in the 66th minute, but Greek striker Angelos Charisteas saved a point with his ninth goal of the season.

ADO's Mark de Vries was sent off with a red card in the 87th minute.

With eight matches to go, PSV are a step closer to the championship as the gap with Ajax now stands at seven points. AZ and Twente follow at eight and nine points respectively.