Barcelona v Celtic: key battles
What's left to say about Messi? The Argentinian superstar hit his 21st Barcelona hat-trick as 10-man Barca won 5-4 at Deportivo La Coruna to confirm a widely-held belief that he is the greatest player ever. Messi does not play as an orthodox centre-forward but is likely to be the first point of contact for Wilson. The former Notts Forest centre-back has established himself as a regular this season and will be hoping that the calf complaint which kept him out of the 5-0 weekend win over St Mirren is fully healed.
There are few better players in world football than Iniesta. The 28-year-old midfielder has three Champions League medals and five La Liga titles on his CV. And in between two European Championship wins with Spain he scored the winner against Holland in the 2010 World Cup final. Brown has taken another injection to get through his on-going hip complaint but Hoops boss Neil Lennon claims the Scotland midfielder is in the best form of his Celtic career and he will certainly need to be if he is to shackle one of the most creative players of all time.
Barcelona have defensive problems with Gerard Pique struggling with a foot injury and Carlos Puyol, Daniel Alves and Eric Abidal already ruled out. Midfielder Mascherano played in a makeshift Barca central defence along with Alex Song in the 5-4 win over Deportivo at the weekend and his unease showed. Hooper is on the sort of form which can cause the Catalans problems and scored his eighth goal in six games at St Mirren.