Calum Chambers has signed an extended deal at Arsenal, tying down his long term future until 2022.The young defender had only signed a deal last year to play for Arsenal until 2021, but last season saw Chambers impress amongst a defensive crisis at the club - and Emery and our backroom team have seen enough to want the England defender at Arsenal for years to come.Chambers last year seemed to be on the cusp of being loaned or sold, with Laurent Koscielny, Shkodran Mustafi and even Rob Holding ahead of him in the pecking order.But injuries to Koscielny, poor form from Holding and Mustafi suffering a combination of both gave him the game time he needed, and he took the opportunity with both hands, giving assured performances in the last third of the season.Chambers made 12 appearances in the League last campaign, along with 8 games in our Europa League run. It was in stark contrast to the season before that saw Chambers loaned out to Middlesbrough - and ironically, this is where he saved his Arsenal career.His loan spell may have ended in relegation with Boro, but he played the majority of the season as first choice in his preferred position of centre-back, and it allowed Chambers to squeeze into Arsenal’s squad for last season.Chambers’ contract extension is an indicator of his new stature at the club, with new man Sokratis expected to be a starter, the Greek defender will need a regular partner. With Koscielny out until December and Mustafi not convincing, it leaves the door open for Chambers to grab the initiative. This new contract seems to indicate he will be among the first choices - and it is a just reward.The defender, now a full England international, has had an upward career of late. In 2016 he captained the Young Lions to glory in the Toulon tournament, and his aerial ability and strength have vastly improved with the extra minutes on the pitch.Chambers has shown enough to warrant confidence from Emery and the Arsenal people on the training pitch. Surely that is enough for fans to get behind him too.This season will be his biggest yet.