Just two rounds remain before the end of the 2009 MX1 and MX2 Motocross World Championships, starting this weekend at Lierop in The Netherlands.

Both titles are yet to be decided, although that could change this weekend, with Toni Cairoli starting the final four races with a dominant 45 point lead over 2010 KTM's team-mate Max Nagl.

Should the Red Bull Yamaha star hold an advantage of 50 points or more after Sunday's two races then he will have secured the MX1 crown, at his very first attempt, before travelling to the Brazilian season finale.

Nagl has outscored Cairoli at the last three rounds to take the runner-up spot by 30 points from Monster Yamaha's reigning champion David Philippaerts, who is now facing intense pressure for third from LS Motors Honda rider Clement Desalle.

Desalle took his first race win last time out at Loket and is now just two points behind the Italian and a healthy 20 points ahead of Teka Suzuki's Ken de Dycker and Philippaerts' team-mate Josh Coppins.

Martin Honda's Marc de Reuver, who won in Lierop last year, is due to make his comeback to racing this weekend after a training accident forced him to sit out the whole middle part of the season.

Meanwhile, team-mate Kevin Strijbos broke his right tibia and fibula last week and is out for the remainder of the year.

KTM Silver Action's Barragan, who was injured before the French GP and underwent an operation to remove his spleen, will also make his comeback at Lierop.

In the MX2 class, Marvin Musquin holds a reduced 20 point lead over Red Bull KTM team-mate Rui Goncalves - after his mechanical DNF at Loket - with Kawasaki's Gautier Paulin also firmly in the title fight, 28 points from Musquin.

Shaun Simpson, whose injury made machines available for Musquin, will return to action this weekend.