United have explored the possibility of securing Rondon on a longer loan.
However, West Bromwich Albion, his parent club, would have nothing to gain from loaning him for another season given that he is out of contract at The Hawthorns in 18 months time.
Newcastle refused to meet Rondon's £16.5million release clause last summer.
The club's hierarchy vetoed a permanent move for the 29-year-old striker because of his age, and the Venezuela international eventually arrived at St James's Park in a loan swap deal which saw Dwight Gayle join the Championship club.
And United fans quickly took to Rondon, who netted in Tuesday night's 2-1 win over Manchester City.
Rondon has scored six Premier League goals so far this season.
Newcastle's position on a permanent move for Rondon is not understood to have changed, despite Benitez's belief that he can play at the top level for several more years.