The 35-year-old Mertens and 33-year-old Witsel have 239 caps between them and were integral parts of Belgium’s ‘golden generation’, which fell short of both World Cup and European Championship success over the last decade.
The pair were left out as Tedesco signalled a new direction for the team after replacing Roberto Martinez as coach after Belgium’s horror World Cup in Qatar late last year where they had lofty aspirations but tumbled out in the group stage.
Captain Eden Hazard, defender Toby Alderweireld and reserve goalkeeper Simon Mignolet have since announced their retirement from international football, although Belgium’s most capped international Jan Vertonghen keeps his place. He is 35 years old and has 145 caps.
"It’s not about age," Tedesco told a Friday news conference, saying the door remained open for midfield linkman Witsel, who has not been playing regularly at Atletico Madrid this season.
"I went to Madrid and met him there a few weeks ago. I called him yesterday to explain my choice. This was not an easy choice. He has done so much for the Red Devils. The door is not closed to him and I told him that. Now I want to try new players and see their potential," the new coach added.
Teenage Southampton midfielder Romeo Lavia is the only new call-up, however.
Mertens was dropped because of a lack of match fitness while Michy Batshuayi and Youri Tielemans are injured.
Belgium play their opening Euro-2024 qualifier in Stockholm against Sweden next Friday and then meet the Germans in Cologne on March 28th.
Tedesco said a replacement for Hazard as captain was still to be decided.
"I have my own ideas but I first want to talk to the players about it," he said.
Squad:
Goalkeepers: Koen Casteels (VfL Wolfsburg), Thibaut Courtois (Real Madrid), Thomas Kaminski (Blackburn Rovers), Matz Sels (Racing Strasbourg)
Defenders: Sebastiaan Bornauw (VfL Wolfsburg), Timothy Castagne (Leicester City), Zeno Debast (Anderlecht), Wout Faes (Leicester City), Thomas Meunier (Borussia Dortmund), Arthur Theate (Stade Rennes), Jan Vertonghen (Anderlecht)
Midfielder: Yannick Carrasco (Atletico Madrid), Kevin De Bruyne (Manchester City), Charles De Ketelaere (AC Milan), Romeo Lavia (Southampton), Orel Mangala (Nottingham Forest), Amadou Onana (Everton), Dennis Praet (Leicester City), Alexis Saelemaekers (AC Milan)
Forwards: Jeremy Doku (Stade Rennes), Romelu Lukaku (Inter Milan), Dodi Lukebakio (Hertha Berlin), Lois Openda (Racing Lens), Leandro Trossard (Arsenal).
