Northern Irishman Robbie Weir was the first summer signing ahead of the 2016-17 season when he agreed an initial two-year deal, with the club having the option to extend his stay for a further year.
He started off with the Larne youth system, though moved to England in 2007 to join the youth set-up at Sunderland. During six years with the Black Cats, Weir came through the academy though failed to make an appearance for the first team.
Loans at York City and Tranmere Rovers gave the midfielder his first taste of professional football, before he joined Rovers permanently in 2011 where he would go on to spend one season at Prenton Park ahead of a move to Burton Albion.
It was during his time at the Pirelli Stadium that Weir enjoyed his most successful years to date, helping the club finish the 2014-15 campaign as League Two winners before securing a second consecutive promotion a year later as the Brewers reached the Championship for the first time in their history.
Weir was appointed Orient captain ahead of the 2016-17 campaign by manager Andy Hessenthaler in July 2016.