On Friday, il BiancoNero (via CalcioMercato.com) reported Juve sporting director Fabio Paratici has made Mandzukic available in transfer talks ahead of the 2019-20 season after the Red Devils' efforts to land the Croatian forward fell short last summer.
il BiancoNero also claimed Mandzukic is "ready to join United" and "positive about the offer" they have given.
Mandzukic's production has dipped across four years with Juventus after high-scoring stints with fellow European giants Bayern Munich and Atletico Madrid.
The 33-year-old veteran has tallied 44 goals across 162 appearances in all competitions for the eight-time reigning Serie A champions. He scored 68 times in 131 matches for Bayern and Atletico.
Further details about the ongoing talks between Juve and United are unknown. It's uncertain whether it's a potential two-for-one deal, whether the Vecchia Signora are seeking more in return and if the sides are close to an agreement with the term set to begin.
Lukaku scored just 15 goals in 45 appearances for United last season after four straight years with at least 20 goals with Everton and Manchester United.