The Barclays Premier League duo sent scouts to watch the highly-rated Partizan Belgrade star, and both are considering a formal inquiry.
In demand: Petrovic (left) has attracted interest from across Europe
The 21-year-old, who plays in midfield, has courted interest from across Europe, with Inter Milan and Juventus among the clubs keen on theSerbia star.
However, United and Spurs are thought to be leading the race to sign Petrovic, who's been a key member of Partizan's table-topping side.
The 6ft 4" star featured in his side's defeats to Arsenal during the recent Champions League group phase, and is said to be keen on a move to England.
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