UPDATE 2-Soccer-Atletico win to improve Champions League chances

* Atletico beat Valencia 1-0 to close in on Champions League

* Real Mallorca see off second-string champions Barca 2-1

* Guardiola rests key players with title already won

(Updates with late result, adds Guardiola quotes)

MADRID, May 17 (Reuters) - Diego Forlan stroked in a penalty to give Atletico Madrid a 1-0 Primera Liga win over visiting Valencia on Sunday and improve their chances of a lucrative place in next season's Champions League.

Barcelona clinched their first league title in three years on Saturday and Real Madrid are assured of second place with two matches left.

Third-placed Sevilla (64 points) and Atletico, who climbed to fourth (61), have the best chance of grabbing the remaining two spots in Europe's top club competition and Valencia and Villarreal are still in the hunt in fifth and sixth on 59.

Atletico took the lead from the penalty spot in the 29th minute at the Calderon.

Sergio Aguero burst through the centre and took the ball round Valencia goalkeeper Luis Cesar Sanchez before tumbling to the ground and the referee pointed to the spot.