West Ham United will decide within the next two days whether to appeal to the international Court of Arbitration for Sport (CAS), over an FA tribunal ruling which could leave them paying out £30m to Sheffield United over the Carlos Tevez affair.

The east London club are actively considering appeals to Fifa or CAS over the tribunal's findings, but the latter is the most likely option and such a course of action would reflect the indignation felt by some in the upper echelons of the club over a decision they believe could allow other relegated sides to seek redress through the courts.

It has always been Sheffield United's case that West Ham saved themselves from relegation – and condemned the Blades to the drop – in the 2006/07 season by fielding two players, Carlos Tevez and Javier Mascherano, who were owned by third-party companies in breach of Premier League rules. Tevez, in particular, shone during West Ham's run-in, scoring the winner at Manchester United which saved his side from the drop. After an 18-month struggle to prove West Ham are financially liable, the Blades' chairman, Kevin McCabe, has finally won his argument and last night the view among many West Ham fans was that the club should hand over a £30m cheque immediately to bring an end to an ignominious chapter in the club's history. There is a feeling in some quarters that the Icelandic owners may agree that stringing out the saga even longer is not desirable.

If the appeal route does not prove a viable option, West Ham are privately resigned to paying out the £30m Sheffield United are seeking. The judicial process to establish how much the club must pay to the Blades may take several months – with an initial directions hearing next week. West Ham will put forward mitigating factors to limit the damage, but McCabe is confident of his £30m figure. It has been computed from the loss of TV earnings, reduced transfer fees, season ticket sales, merchandising and "lost business opportunities" after relegation.

The thrust of any West Ham case laid before CAS, in Lausanne, Switzerland, would mirror that which has been laid before the FA Tribunal by its own lawyers in recent months: that the failure to record the details of the ownership structures for Tevez and Mascherano cannot account alone for the Sheffield club's failure to stave off relegation.

But there is also a feeling in some quarters at West Ham, which has no right of appeal to the FA tribunal itself, that the issue at stake is a bigger one for football. One scenario being floated yesterday was the prospect of Watford seeking compensation over the freak goal which the referee, Stuart Attwell, awarded them against Reading last Saturday if the three points they might have secured proves the difference between relegation and survival.

West Ham, also indignant that a judgment made available to both sides on Friday afternoon on the basis of confidentiality, was apparently leaked from the Yorkshire end, have already been fined £5.5m by the Premier League for irregularities in Tevez's and Mascherano's registrations. But West Ham were not deducted points by the league and Tevez was cleared to play in the club's remaining games of that season. On the final day, the Argentine scored the winning goal against Manchester United, his current club, to confirm West Ham's Premier League status.

The Blades' appeal against the Premier League's refusal to deduct points was rejected by an FA arbitration panel chaired by Sir Philip Oton, but that panel concluded that it would have reached a different decision to the Premier League's, had it been in judgment – a verdict which gave the Blades hope. The club turned its attentions to a compensation fight through a second FA tribunal, chaired by Lord Griffiths, which has now concluded it had "no doubt that West Ham would have secured at least three fewer points over the 2006-07 season if Carlos Tevez had not been playing for the club."

The tribunal panel does not recognise West Ham's unilateral termination of Tevez and Mascherano's flawed initial contracts, ordered by the Premier League, which meant that they played the last three games of the 2006-7 season under terms acceptable to the League. The tribunal panel added in its ruling that "even over the final two games of the season, West Ham would have achieved at least three points less overall without Mr Tevez."

The Blades, whose financial demands include £4m for Phil Jagielka, who was sold cheaply as a result of the drop, also raised the question of a further intervention by the Premier League, though this seems unlikely.

How figures add up

£36.8m

Amount West Ham received in television revenue during 2007/08.

£49.4m

West Ham's estimated turnover for the year up to May 2007.

£34.6m

Amount spent by West Ham on transfers since May 2007.

£6.25m

Amount spent by Sheffield United since May 2007.

15%

Decrease in Sheffield United's average attendance from 2006/07 to 2007/08.

£59.1m

Value in transfer fees of West Ham's current first-team squad.

£9.5m

Value of Sheffield United's current first-team squad.