Champions were crowned in four major European leagues as Inter Milan, Lyon, Celtic and Olympiakos all won their national league titles over the weekend.

Italian World Cup champion Marco Materazzi, who was on the receiving end of Zinedine Zidane's head butt in the World Cup final, scored both goals to give Inter Milan a 2-1 win at Siena on Sunday and clinch its 15th Scudetto. It is Inter's first title on the field since 1989. Inter was awarded last year's title when a sports tribunal revoked Juventus' title win in the fallout from the country's match-fixing scandal.

Like Inter, Lyon had blown a chance to clinch the title at home on Wednesday and celebrated with champagne on Saturday night at its Auxerre hotel when second-place Toulouse lost at home to Rennes, 3-2. Lyon, which was held to a 0-0 tie at Auxerre on Sunday, clinched a sixth Ligue 1 title -- a record for a major European league. Only Rosenborg has done better in Europe, collecting 13 Norwegian titles from 1992 to 2004.

Celtic clinched back-to-back Scottish Premier League titles on Sunday when Japanese star Shunsuke Nakamura scored with a brilliant free kick in stoppage time to seal a 2-1 win at Kilmarnock.

Olympiakos made sure of its ninth Greek league title in 10 years when it beat Kerkyra, 3-1.