The Mozambique international was a target for the Black Cats during the summer, when they made an offer worth more than €30 million, with bonuses potentially taking the package close to €40m. Sporting rejected the proposal, maintaining that their valuation had to be met before they would consider selling.
According to A Bola, Fonte is now a driving force behind Sunderland's renewed pursuit. The former Portugal international, who joined Régis Le Bris' coaching staff after ending his playing career with Casa Pia, believes Catamo could make an important contribution as the English side attempt to turn around their season.
Sunderland's current predicament is a considerable contrast to their previous campaign. After defying expectations to finish seventh in the Premier League and qualify for the Europa League in 2025/26, they now sit bottom of the table and are facing a fight to retain their top-flight status.
Catamo's versatility and attacking qualities are viewed as potential assets in that battle. The 25-year-old can operate on either flank and has established himself as an important player for Sporting, where he wears the number 10 shirt.
The Portuguese club remain reluctant to lose him. Their asking price is still understood to be €40m, while his contract runs until 2029 and includes a €60m release clause.
Sporting have already made an offer to extend his agreement until 2031, underlining their preference to keep the winger rather than cash in during the winter window.
There is also a financial consideration for Catamo. During the summer negotiations, the salary offered by Sunderland was reportedly five times what he currently earns in Lisbon, making the prospect of a move to England attractive from that perspective.
His performances have been mixed over the course of the current campaign. Catamo made an impressive start, registering two goals and three assists across his first five appearances, but a subsequent dip in form saw him left out of the starting line-up against Casa Pia.
He came off the bench for the final 28 minutes of that match and scored in stoppage time, taking advantage of an empty goal after goalkeeper Patrick Sequeira had gone forward for a late attacking opportunity.
Sporting are also considering the potential impact of losing other players during the January window. Australian youngster Nestory Irankunda could be called up for international duty at the Asian Cup, potentially leaving the club short of options and prompting them to consider reinforcements.
Sunderland's interest therefore comes at a potentially important moment for both sides. The English club are expected to revisit the possibility of signing Catamo, but Sporting's €40m valuation and desire to extend his contract mean any deal will require a significant effort.