Crystal Palace have confirmed the signing of Patrick van Aanholt from Sunderland.
The 26-year-old left-back arrives for a fee Press Association Sport understands could rise to £14million, and having signed a four-and-a-half year contract becomes their second recruit of the January transfer window after the £12million capture of Jeffrey Schlupp.
According to Palace boss Sam Allardyce, Van Aanholt played an "instrumental" role in Sunderland unexpectedly surviving relegation under Allardyce last season, and the Holland international will go straight into the Eagles squad for Tuesday's trip to Bournemouth.
Allardyce also appeared to rule out a further approach for Arsenal's Carl Jenkinson, despite chairman Steve Parish "negotiating at least five or six deals", and revealed free agent Martin Caceres could arrive after Tuesday's transfer deadline.
"He (Van Aanholt) is a player that brings something to the team we have not got and hopefully he has an instant impact," Allardyce said.
"We had great success together at Sunderland where he was instrumental in keeping them in the Premier League last season.
"He will add pace and energy to our team, has strong defensive qualities and has the added ability to score and create goals. He will help in both departments."
In the knowledge Van Aanholt's arrival was imminent, after Saturday's 3-0 FA Cup fourth-round defeat by Manchester City, Allardyce spoke of his desire to recruit a central defender.
A fee with Arsenal for Jenkinson had long been agreed before his transfer was held up by an inability to agree personal terms, and asked if there had been any progress with the full-back, Allardyce said: "There are other priorities for us that we are looking at.
"Whether it happens before the end, I can't say whether that will get done or not.
"We are still hunting for at least two players. We are sitting with as many people as we can. I spent most of (Sunday) sitting with the chairman (Steve Parish) negotiating five or six deals to see if we can bring anything through the door."
Reports persist that relegation-threatened Palace, who on Tuesday visit Bournemouth in the Premier League, could yet sell Andros Townsend to Newcastle, and Chung-yong Lee.
However Allardyce, who has so far overseen only one win in eight since his appointment in December, said he had no plans to sell any of his players and that Palace's squad could be imminently strengthened by Caceres' arrival and Schlupp's unexpectedly swift return from injury.
"We are after targets in," he said. "In terms of outs, I need to speak to the chairman if that is a consideration. Obviously (Townsend's departure) has been mooted for a couple of days but I'm not sure the chairman has had any contact with Newcastle.
"I haven't heard we have had a bid for Chung.
"Martin (Caceres) is only something that may happen after the window has finished because he is tied to no football club. He is a quality player but has been dogged by a few injuries.
"It's not as bad as we feared (with Schlupp). He will probably be unavailable for Bournemouth, but should be back against Sunderland on Saturday."