(Adds Mandanda signing, changes slug)
LONDON, July 1 (Reuters) - Crystal Palace and Newcastle United traded players on Friday, with winger Andros Townsend moving to London for 13 million pounds ($17.3 million) and striker Dwight Gayle joining the recently relegated club for 10 million pounds.
Palace also announced the signing of French goalkeeper Steve Mandanda on a free transfer from Olympique Marseille.
Townsend, who just missed out on inclusion in England's 23-man squad for Euro 2016, has signed a five-year deal at Selhurst Park, the London club said.
The 25-year-old former Tottenham Hotspur winger only signed for Newcastle last January in a bid to secure regular first-team football and save the club from relegation from the Premier League.
Townsend scored four goals in his 13 appearances at St James' Park.
"It was a pretty easy decision to choose Crystal Palace because of the direction they're heading," he told the Crystal Palace website.
"They play a system that suits wingers and you only need to look at Wilfried Zaha, Yannick Bolasie and Jason Puncheon to see how they've excelled and how influential they are for Palace. I want to be a part of that and help this club reach its potential."
Gayle, 25, has signed a five-year deal. He has been Palace's top scorer for the past three seasons, netting 25 times despite finding his first-team opportunities restricted at Selhurst Park.
He is Rafa Benitez's second signing this summer, following the arrival of Gent goalkeeper Matz Sels. ($1 = 0.7511 pounds) (Reporting by Neil Robinson, editing by Ed Osmond)