So far this season, Everton have failed to get the best out of two key men; that must change.
One issue has been present throughout Everton's early optimism and subsequent disappointment in the opening months of this season - and it remains a problem now.
It is a question Sam Allardyce must now answer as he steps into the Goodison Park job, having seen Ronald Koeman and David Unsworth both fall short.
The new man's first call will undoubtedly be to decide that there must be a system to suit both players, with the decision to drop either the club's talisman or their record signing unthinkable.
Rooney delivered his best performance of the season as he netted a hat-trick against West Ham United on Wednesday, playing from a deeper midfield role.
But that was in a midfield three and Sigurdsson was still forced to play in an unnatural wide left position.
Not yet this season have Everton fans seen Rooney and Sigurdsson working effectively in tandem.
If this side are to realise their immense potential, Allardyce must discover a set-up that suits both players and the team.