Best friends for years - going back to when they played for different clubs and lived near each other in Amsterdam - the Belgian pair have been key players for us this season.
And while Mousa's recent performances against the likes of Arsenal, United and Juventus drew high praise from high-profile pundits, Jan's consistent displays have been somewhat under the radar.
Now Belgium's most capped player, Jan is approaching 250 appearances for Spurs. He recently missed the Premier League match at Palace through injury, ending a run of 40 PL starts over a year. He was straight back in against Huddersfield.
Mousa said: "Jan's playing amazing football and we all know this, it’s not something new.
"I’ve known Jan for so long, since I was young. I always said, for me, I couldn’t think of a better defender than him.
"It’s not only because he’s my friend. His quality on the pitch...like myself, he’s improved over the years. I believe Jan is playing unbelievable football. I hope he gets the recognition he deserves because for me, he’s a fantastic player."