Alexei Shirov has not been in particularly good form in the last year, but can always be counted on to be entertaining. However his efforts at seeking complications have so far been thwarted by the World Champion's precise play and mastery of all types of position.
In game 4 he was more successful with a cautious defensive display that at least stopped the rot.
Tomorrow he will need to win both games to catch Anand.
The games are 60' plus 30" per move. One characteristic of the series of matches in Léon is that the players have access to computers during their games. This particularity is referred to as Advanced chess.
The final pair of games will be tomorrow afternoon.
The official site gives more information: