Everton defender Seamus Coleman has signed a new five-and-a-half-year contract with the Premier League club. Republic of Ireland international Coleman, 24, has committed to David Moyes\' team until 2018 after being rewarded with an improved deal after some dynamic displays at right-back and in midfield this season. \"I\'m glad to get it all done and to sign for so long at a club like Everton is a great achievement. I want to be here for as long as possible,\" Coleman told Evertontv. \"Signing a contract here is fantastic and I\'m really looking forward to the next couple of years. I\'m going to keep working as hard as I have done since day one and keep improving every day in training to impress the manager. I\'m really happy to have signed for the length of time that I have.\" There was also some bad news for Everton, though, with midfielder Darron Gibson ruled out for a month after suffering a thigh strain. Gibson missed Everton\'s 2-1 defeat against Chelsea on Sunday as a result of the problem and Toffees manager David Moyes confirmed on Monday that the Republic of Ireland international won\'t be back in action until February. The 25-year-old spent more than two months on the sidelines earlier in the season with a similar problem and missed 10 Premier League games. \"I think he\'s going to be out for about four weeks,\" Moyes said. Gibson\'s absence is a significant blow to Everton, who are challenging for a top four finish, as Moyes is already without Kevin Mirallas, Tony Hibbert and Seamus Coleman due to injuries. Source:FIFA