If Atletico Madrid's 2013 King's Cup triumph was a shock and their 2013-14 La Liga title a surprise, few would raise an eyebrow if Diego Simeone's ruthlessly efficient side were to win another major trophy.
Atletico have quietly been going about their business while Spain's big two, Real Madrid and Barcelona, have stuttered in recent weeks.
Simeone's team are level on points with champions Barcelona at the top of La Liga after 15 matches. Real are five points adrift in third.
Atletico, characterised by a mean defence, talented midfielders such as Koke and Yannick Carrasco and skilful forwards like Antoine Griezmann, will look to join Barca in the King's Cup last 16 when they host Reus Deportiu on Thursday.
They should have little trouble getting past the third-tier minnows having won this month's first leg at Reus 2-1 with a second-string side.
Atletico are also through to the last 16 of the Champions League, having won their group, and were drawn on Monday to play Dutch side PSV Eindhoven.
"We have to be up there getting under people's skin," Simeone told a news conference after Sunday's 2-1 comeback La Liga victory at home to Athletic Bilbao.
"And if the big boys slip up then we have to make the most of it," added the former Argentina captain.
A major reason for Atletico's strong start to the season has been the form of Griezmann who netted a superb goal to seal Sunday's victory.
Griezmann has scored eight in La Liga and another four in the Champions League, with Simeone transforming him from a promising youngster into one of Europe's most feared forwards.
"We know Griezmann is a unique player and that when he touches the ball it's almost certain to go in because his level of efficiency is incredible," said midfielder Saul Niguez who scored Atletico's equaliser against Bilbao.
Barca's last-32 tie was brought forward due to their participation in this week's Club World Cup in Japan while Real's bid was ended when they were expelled for fielding an ineligible player against third-tier Cadiz.
In other second legs this week, Valencia and new coach Gary Neville take a 3-1 lead into their game at home to third-tier Barakaldo when the former England defender could get his first win at the third attempt.
