Atletico in the market for midfielder, says Simeone

MADRID (Reuters) - Atletico Madrid have been one of the most active La Liga clubs in this transfer window but coach Diego Simeone said on Friday they may not be done yet and want another midfielder. After finishing third behind champions Barcelona and second-placed Real Madrid last term and qualifying for the Champions League, Atletico sold Croatia striker Mario Mandzukic to Juventus and Turkey playmaker Arda Turan to Barca. Signings include Colombia striker Jackson Martinez, Argentine forward Luciano Vietto, Belgium midfielder Yannick Carrasco and Montenegro defender Stefan Savic, while playmaker Oliver Torres has returned from a loan spell at Porto and Filipe Luis was bought back from Chelsea after one season. Hopes are high that Atletico can again challenge for the Spanish league title after they stunned Barca and Real to win La Liga in 2013-14. They begin their latest campaign at home to promoted Las Palmas on Saturday. Asked about the possible arrival of another midfielder, Simeone told a news conference the club was working on it. "We are open to everything that might happen," the former Argentina captain added. "We are very pleased with the squad we have and if someone comes to help out they will be welcome. And if someone leaves I hope that's the best thing for that player." Simeone revealed that Martinez, who Atletico signed for 35 million euros (25 million pounds) from Porto, would start Saturday's match alongside France forward Antoine Griezmann, with Torres in a four-man midfield with captain Gabi, Koke and Tiago. (Reporting by Iain Rogers, editing by Ken Ferris)