Tottenham have clinched a move for Serge Aurier.
Aurier clinched his move on deadline day, and will replace Kyle Walker at right-back.
Aurier is a two-time French title winner and has played at the World Cup with Ivory Coast.
Cascarino said that opposition attackers will not relish playing against the full-back.
He said: "The 24-year-old right back is unbelievable at getting up and down the line and he will fit perfectly into the way Tottenham play.
"He is lighting quick, the kind of player whose burst of pace will get the crowd on its feet. Nobody will want to take him on, one-on-one, because he gets over wingers like a rash.
"If Kieran Trippier is better on the ball, Aurier will push him for a regular pace because of that speed."
Tottenham also have Kyle Walker-Peters adding depth at the position, but the chance to add Aurier was an opportunity they felt they could not turn down.
Losing Kyle Walker's pace would have been a concern, but Aurier coming in suddenly negates those concerns.