Adams said that he is "very worried" about the damage Dembele could cause for Spurs, who he feels have closed the gap somewhat with their transfer business.
"I think they've closed the gap, Tottenham, for sure," he told Sky Sports News. "Maybe Arsenal have come back to them a little bit. They're definitely stiff opposition.
"Dembele, I saw him when he was a kid at Willem II in Holland. He can pick up the ball and hurt them - Christian Benteke did it for Aston Villa.
"Dembele sits in the hole - has the midfielder got him? Has the defender got him? He can sit in that hole and really hurt Arsenal on the counter-attack, so I'm very worried."
The game on Sunday kicks off at 4pm.