Viduka has criticised former club Middlesbrough's reluctance to open contract talks last January, suggesting he was happy at the Riverside but needed to know where he was going to be playing this season.
Viduka: "It's disappointing when you have played for a club and you want to do well, and it comes to a point where you don't know if you're staying or going, with six months of your contract left.
"The club does not look after you in that sense. The club gets a lot of situations like that.''
Gareth Southgate still insists he did everything in his power to keep the Australian on Teeside, but his efforts were all far too late.
Viduka had a winning start to his Newcastle career as the Magpies strolled past Bolton.
On the opening day of the English Premier League, Newcastle manager Sam Allardyce made a sweet return to the Reebok Stadium, as two goals from Obafemi Martins helped his side to a 3-1 victory.
Charles N'Zogbia also found the back of the net for the Magpies, while Nicolas Anelka scored a consolation goal for the home side.
Viduka, who transferred from Middlesbrough in the off-season, nearly put the visitors ahead after just five minutes, taking advantage of a defensive mix-up only to see his shot blocked by Bolton's Gerald Cid.
Newcastle took the lead in the 11th minute when N'Zogbia drove in a free-kick from the right which eluded the Bolton defence and goalkeeper Jussi Jaaskelainen.
Ten minutes later, Martins beat Jaaskelainen with a superb overhead kick off a cross from James Milner.
Martins made it 3-0 in the 27th minute with his shot from 20 metres taking a deflection off defender Abdoulaye Faye to leave Jaaskelainen stranded.
Anelka scored off a reverse pass from Kevin Nolan in the 50th minute but it was not enough for the home team.
Viduka, who captained the Socceroos in their recent Asian Cup campaign, was substituted by Shola Ameobi after 72 minutes.