Onyewu won't be joining Rangers it seems
Onyewu was invited on the Gers' pre-season tour of his homeland, and played 66 minutes of Wednesday night's friendly win against Charleston Battery.
However, the 34-year-old was culpable for the goal scored by Battery playmaker Attaulah Guerra, and the report claims Rangers will explore other options.
Warburton was reportedly set for talks with Onyewu
It is said that Mark Warburton, the Ibrox boss, was due to hold talks with Onyewu after the club's final stateside training session, though he is not expected to return to Glasgow with the rest of the team on Friday.
Onyewu, who's played for a string of European giants including AC Milan, Standard Liege and Sporting Clube de Portugal, has offers to remain in the US, the Daily Record reports.
Onyewu playing for AC Milan
Warburton has added Clint Hill and Lee Hodson to his back line this summer, and capturing another centre-back would ensure he has, effectively, two players for every defensive position - given Hill's ability to play left-back.
Former Watford stopper Adrian Mariappa was a rumoured target earlier this month, but a deal for the 29-year-old is said to have stalled (Daily Mail).
Mariappa worked under Warburton at Watford