Spurs are one point above the Serbian Superliga leaders in Group B, after thrashing them 5-0 in the first leg.
Red Star Belgrade are 4/1 to win with Betfred to add to Spurs' woes.
Alessandro Del Piero now holds the record, needing just 26 games to tally 20 Champions League strikes while Ruud Van Nistelrooy (27), Filippo Inzaghi (28), Mario Gomez (32) and Rivaldo (33) round out the remaining top five.
Harry Kane has also flown to the Serbian capital after missing the design at Everton with sickness, revealing he had given Son "a hug" on his return to training on Monday. Son picked up the ball and hit the top post, and after several deflected shots, finally Giovani Lo Celso shook the net for 1-0.
Last goal was scored in the 85th minute by Christian Eriksen who entered fifteen minutes earlier from the bench.
"I can guarantee that everyone here will feel safe", Red Star boss Milojevic said.
It then fell to Lo Celso.
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In return, Beijing wants the U.S.to do away with new import taxes due to take effect December 15 on goods including smart-phones. He cautions that companies shouldn't assume that they will receive a permit, but he expects that "quite a few" will be approved.
And, y'know, mad things like that very rarely happen.
Red Star supporters were not allowed to buy tickets for the game at Tottenham after Uefa, European football's governing body, charged the club as a punishment for fans' racist abuse against HJK Helsinki in July.
With Spurs looking comfortable, the nail was officially hammered into the Red Star coffin just four minutes later as Son finished off a superb flowing move to ensure the 1,200 traveling fans who will make the long trip home will be a happy ol' bunch.
It is only Red Star, after all.
Tottenham last won away from home when it beat Ajax in last season's Champions League semifinals. But you can't begrudge people seeing their side play well.
The England skipper helped himself to a brace during last month's 5-0 win against Red Star; a repeat performance would not only go some way to ensuring his side secure a vital three points, but see Kane leapfrog some of the game's greatest marksmen as the quickest to reach 20 tournament goals.
Which prompted some time to think from the Spurs lot.