Champions League preview: Real Madrid v Manchester United
Defence looks set to decide Real Madrid's Champions League round-of-16 clash with Manchester United despite both team's attacking riches.
While the focus for Wednesday's first leg in Madrid will be on Cristiano Ronaldo taking on his former club as well as the Portuguese forward going head-to-head with Manchester United's main marksman Robin van Persie, it is likely the game will actually be decided at the back.
United and Real managed just one clean sheet between them in the group stage of this season's competition - the Premier League leaders defeated Galatasaray 1-0 at Old Trafford back in September.
Real conceded nine goals in their six group stage fixtures, while United - that home clean sheet aside - let in six in five games as they qualified for the knockout stages.
United manager Alex Ferguson has struggled to find the right combination in defence all season and has relied on his team's attacking prowess to win matches, but in Madrid he may revert to a more defensive structure.
Ferguson has traditionally packed the midfield and set his team up in a 4-5-1 formation when travelling away in the Champions League, which could see Van Persie start up front in Madrid with Wayne Rooney either on the bench or in behind the Dutch striker.
Real coach Jose Mourinho will know, however, that his team must take their chances at the Santiago Bernabeu with Van Persie and Rooney in deadly form.
Rooney headed into last week's international break having scored 10 goals in as many games since the start of December and also got on the scoresheet in England's 2-1 friendly win over Brazil, while Van Persie has hit the back of the net 23 times in 31 matches this season.
By comparison, Ronaldo has scored 32 goals in 30 games across all competitions this season for Real.
With goals guaranteed and the teams' respective defences likely to make the difference, Mourinho faces a big problem - first choice goalkeeper and club stalwart Iker Casillas is out with a broken hand.
While Casillas fell out favour with Mourinho before the winter break, it is hard to imagine the Portuguese head coach would not have chosen Spain's leading goalkeeper for the visit of Manchester United, especially considering Real Madrid's poor form.
Mourinho's side have won just two of their past five matches in all competitions and have seven victories in 14 games.
In the same period, Manchester United have not lost and have won 11 times, opening up a 12-point lead in the English Premier League.