Frank expressed his admiration for Tel's progress in recent weeks, citing his strong character, daily training, and ability to adapt to different positions.
Frank acknowledged that Tel has faced criticism, including racist abuse from some supporters, but is pleased with his response to these challenges.
Frank noted that Tel's goal against West Ham was a solid performance, and that his recent games showed improvement in his link-up play and ability to arrive in scoring areas.
The Tottenham manager praised Tel's work ethic and his ability to learn and grow as a player.
Tel joined Tottenham from Bayern Munich for £30M and has since justified his transfer fee under Frank's management.
Spurs will face Aston Villa and Monaco after the international break, and Tel is likely to start in the lineup.