West Ham United's relegation from the Premier League is set to trigger several player exits as the Hammers need to balance the books heading into next season. It is estimated sales between £100m-£150m will be required for the club to clear their debts. Mateus Fernandes is one player attracting major interest from several Premier League sides. Arsenal, Manchester United and Liverpool have all been linked with the player who has a valuation of £80m. The Irons need to clarify which players they will allow to leave the club before they can begin to make additions as they look to get out of the Championship at the first time of asking. And enquiries on some new signings are already being made. According to GIVEMESPORT senior football correspondent Ben Jacobs, the Hammers have made an initial enquiry about signing Josh Mulligan from Scottish Premiership side Hibernian. The 23-year-old joined Hibs last summer and is under contract with the Edinburgh club until 2029. His season was disrupted by a serious ankle injury back in January which required surgery. He returned for the final two games of the campaign against Rangers and Motherwell. In recent days, Hibs head coach David Gray described the player as 'excellent' and 'hard-working' as he praised the midfielder for the manner in which he battled back from his injury. While West Ham have made an enquiry, there is no formal offer as they continue to assess who they will need to sell this summer. Gray has been linked with English clubs before, with both Nottingham Forest and Leeds United credited with an interest ahead of the January window. However, with Mulligan picking up his injury in mid-January, any hopes of a Premier League move were dashed. Mulligan came through the academy at Scottish club Dundee, and had loan spells at Cove Rangers and Peterhead before becoming a first-team regular. He made a total of 122 appearances for Dundee, scoring six goals and providing 10 assists. He earned a move to Hibs last summer and played 33 times for the club, with three goals and five assists. He joined Hibs on a free transfer when his contract at Dundee expired. However, the Easter Road club did pay a compensation package to the Dark Blues as the player came through their academy. That agreement, according to The Courier, contains a sell-on clause. That could result in Hibs putting a slightly bigger price tag on Mulligan if West Ham decide to proceed with a formal bid.