The 24-year-old originally started the campaign on loan at, Aston Villa but his second spell at Villa Park wasn’t as successful as the first, as Dean Smith’s side struggled to deal with the loss of Jack Grealish.
Smith was replaced by Steven Gerrard in a move that saw the United loanee’s game time become more limited.
In two appearances, he mustered eight minutes of professional football as a substitute under the former Liverpool captain.
Tuanzebe completed his move to Serie A on Saturday and was brought on during their 1-0 win over Sampdoria 24 hours later.
Andrea Petagna scored the all-important goal as Luciano Spalletti’s side ended a run of three straight home defeats with the three points keeping them in the hunt for the Scudetto, as AC Milan replaced Inter Milan at the top of the league.
Zlatan Ibrahimovic helped them to the win, stretching the gap between them and the Neapolitan’s to five points.
Tuanzebe came on with 10 minutes to go as they looked to weather the onslaught from the visitors.
Following the win, the England U21 international posted on Instagram in Italian which translated to: “Happy for my first match with Napoli. #ForzaNapoliSempre”
His wait to feature again for the club won’t be too long as Napoli prepare for Fiorentina in the Coppa Italia Round of 16 on Thursday.
Saturday’s announcement of his move away from Old Trafford saw him become the third player this month to depart on loan after Teden Mengi and Ethan Laird embarked on new pastures at Birmingham and Bournemouth respectively.