By SABC Sport
14th August 2024
De Ligt has committed to the club until 2029, while Mazraoui has signed a contract running until 2028.
These additions come at a crucial time for United, who have been seeking to strengthen their defence following the injury of Leny Yoro and the departure of Aaron Wan-Bissaka to West Ham United.
With United currently light on full-back options, Mazraoui's versatility - able to play at both right-back and left-back - adds much-needed depth.
Martinez, who joined United two years ago and has experience playing with Mazraoui at Ajax, expressed his optimism about the new arrivals.
Martinez also shares a history with De Ligt, having joined Ajax shortly before De Ligt left for Juventus in 2019.
Martinez described both players as "special" and is confident they will seamlessly integrate into Erik ten Hag's style of play.
"I'm so excited about Matthijs and Noussair," Martinez told BBC Sport.
"We are here to help them and they are really good players, that's why Manchester United bought them and they will show [that] quickly because they have really good qualities and they like to play football and they are special for our system.
"I think Matthijs will give us a strong personality, playing from the back, defending high, I can't wait to play with him."
The duo could make their debuts in Manchester United's Premier League opener against Fulham on Friday night