Starting his 18th game for the club, and fourth in the cup, Tau was facing top-tier opposition for just the second time, having helped his side beat Anderlecht earlier in the competition, yet knew Genk, who top the Belgian Pro league standings by seven points, posed a different threat altogether.
Yet the South African, who scored a brace in the previous round, would not be overawed by the occasion, taking just 17 minutes to get himself on the scoresheet as he somewhat miscued his left-footed volley on goal before swivelling and slotting home with his right foot to give his side the early lead, bagging his fourth goal in the competition and seventh overall for his Belgian club.
Union would concede just after the break, yet re-took the lead through Roman Ferber, this time Tau providing the assist – his fifth of the season – as Union had 20 minutes to hold on to a famous win. Yet Zinho Gano, scorer of Genk's first, levelled matters on 75 minutes, with the two sides then ending the 90 minutes, and then 120 minutes, all square at 2-2 as a penalty shootout ensued.
With the penalties all level at 2-2 after one miss apiece, Tau coolly slotted his spot-kick to make it 3-2, and following Genk’s miss and teammate Faiz Selemani’s conversion, Union emerged 4-3 victors, famously knocking out their illustrious opponents to reach the last four of the competition, a tournament the club last won in 1914.
In France, two other South Africans were also in cup action as Lebo Mothiba came on in the 76th minute of Strasbourg’s Last 16 Coupe de la Ligue clash against Olympique Marseille, which finished 1-1 after regulation time as the match was decided via penalties. Mothiba calmly struck his side’s third spot-kick as they won 4-2, earning a quarter-final date with Olympique Lyon in the next round.
In a third match of the evening that involved a South African that also went to penalties, midfielder Lebogang Phiri played the entire duration of the game as league strugglers Guingamp took Nice to penalties following a 0-0 draw, winning 3-1 via spot-kicks to advance to the last eight, where a difficult tie against giants Paris Saint-Germain awaits.
Bongani Zungu remains sidelined through injury, but will not feature in the latter stages of the Coupe de la Ligue after his club Amiens bowed out of the competition with a 3-2 loss to Lyon.