The Belgian international team-mates have played a key role as we've pushed up to fifth in the Premier League and continue to compete in all three cup competitions.
Jan has started our last nine Premier League matches alongside Federico Fazio and we've lost just once, at Chelsea.
Meanwhile, Nacer took his goal tally to nine in all competitions with the opener in Monday night's 1-1 draw at Burnley in the FA Cup.
That followed a fine display in the 5-3 win against Chelsea when Nacer scored once and set-up two goals on a New Year's Day to remember at the Lane.
"Nacer is a great player," said Jan. "Last season he had some injuries but he's worked hard to come back fully fit.
"His performance against Chelsea was the best I’ve seen from him and I’ve played with him many times. I’m happy he can show the supporters and everyone else what he’s capable of. I’m a big fan."
We return to Premier League action at Selhurst Park in Saturday's 5.30pm kick-off.
Palace impressed in a goalless draw at the Lane on December 6 and now have a new manager in Alan Pardew, who took over last week.
"They were very good at the Lane, very compact and disciplined and with good players up front, lots of qualities," said Jan.
"They’ve changed manager and they will do everything to win against us because it’s their first home game under their new manager.
"But we’re in good form ourselves and we need to remember that. Hopefully we’ll continue that on Saturday."