Arsenal and Chelsea could be forced to postpone their December 26 Premier League fixtures because of a strike planned by London Underground train drivers which threatens to bring the capital to a halt.
Arsenal are due to play Wolverhampton Wanderers at the Emirates on the Boxing Day bank holiday while Chelsea are scheduled to meet neighbours Fulham at Stamford Bridge in the capital's other Premier League match.
The strike could also affect lower division games with the Championship (second division) matches between Watford and Cardiff City and Millwall and Portsmouth also under threat.
Leyton Orient's match with MK Dons and Brentford's clash with Bournemouth in League One (third division), as well as the League Two (fourth division) fixtures between Wimbledon and Oxford United and Dagenham & Redbridge and Barnet could also be postponed.
In a statement Arsenal said: "We are closely monitoring the situation together with all the relevant agencies including the Metropolitan Police, Transport for London, London Underground, The Premier League, Wolverhampton Wanderers FC and Islington Council.
"The paramount concern to Arsenal Football Club is the duty of care we have toward the Arsenal supporters, Wolverhampton Wanderers supporters, matchday employees and indeed everyone who is planning to attend this match."
The planned strike is the result of a dispute over workers' bank holiday pay but the legality of the walkout has been challenged by the transport authorities and will be decided in the High Court in London Wednesday.