The Dutchman is back in the Eredivisie after failing to make an impact at St James’ Park, and is currently the top scorer in the division alongside Dirk Kuyt with 10 goals in 11 games.
And reports claim that this form has alerted the Saints, who are keen to offer him a route back to the Premier League.
De Jong was influential in PSV’s title success last term, even though Memphis Depay stole the headlines.
Now 25, it was close to two years ago that the nine-cap Netherlands international was a Newcastle player – he joined them on loan from Borussia Monchengladbach for the back end of 2013/14.
Interestingly, De Jong starred for now Magpies chief Steve McClaren while at FC Twente.