West Ham were held to a 1-1 pre-season draw at Boreham Wood on Tuesday night.
The Hammers dominated the start of the match and took the lead when Sam Baldock found the back of the net in the 27th minute.
Sam Allardyce's men couldn't hold on for the win as Inih Effiong struck to secure a draw for the non-league side.
Celtic began their pre-season programme with a goalless draw away to Bundesliga side Augsburg.
In front of around 4,000 fans at the SGL Arena, the hosts had the better of the game but could not find a way past Hoops keeper Fraser Forster.
Daryl Murphy hit the post for the Scottish Premier League side as the match petered out into a draw.
SPL newcomers Ross County drew 1-1 with First Division side Raith Rovers in Kirkcaldy.
Confusion in the home defence allowed Sam Morrow to put County ahead in the eighth minute but the impressive Grant Anderson crossed for Brian Graham to head an equaliser in the 16th.