Complex sentence: The strongest tournaments up to now have been of category XXI, for example the XXVI edition of the Linares chess tournament, played in february-march 2009, had an Elo average of the eight participants of 2756 points.
Split into simpler sentences: The strongest tournaments up to now have been of category XXI. For example the XXVI edition of the Linares chess tournament, played in february-march 2009, had an Elo average of the eight participants of 2756 points.