Bedfordshire police said a 25-year-old man had been arrested in Derby on suspicion of attempted murder after Davenport was attacked in the early hours of Saturday at the home of his mother in Bedford, 50 miles north of London.
A police spokeswoman said a 19-year-old man had also been arrested following the incident, in which the player was stabbed in both legs and his 49-year-old mother was also injured.
Davenport, a former England Under-21 international, underwent emergency surgery on Saturday morning but his injuries were not thought to be life threatening, according to police.
A spokesman for the hospital said: "His condition is serious but stable and his mother is in a stable condition."
Davenport, 26, moved from Tottenham Hotspur to West Ham two years ago and the clubs met in Premier League match on Sunday which Spurs won 2-1.
West Ham manager Gianfranco Zola said after the match: "The doctor has told me his condition is stable but we will know more in the next few days. We are very close to him and our thoughts are with him."
Spurs manager Harry Redknapp who signed Davenport on loan at Southampton five seasons ago, added: "I know Calum very well. He is a quiet boy, an inoffensive lad and I am really sad to see what has happened to him and his mum and everyone at Tottenham sends him our best wishes and hopefully he will pull through and be OK."
Davenport played eight Premier League matches on loan at Sunderland last season and after starting his career at Coventry City he also played on loan, for Redknapp at Southampton, and at Norwich City and Watford.
He did not play in West Ham's season-opening match against Wolverhampton Wanderers last week and, before the attack, was not expected to play against his former club Spurs on Sunday.
