Watch : Roger Federer mesmerises crowd with incredible sportsmanship against Alexander Zverev

During the second-round match in the Hopman Cup in Perth, Australia, against Germany's teenage sensation Alexander Zverev, Zverev sent a serve trying to stay in the set at 5-6, only to be called long. Federer, who had left the serve, however, immediately told his opponent that his serve was not long. Furthermore, he encouraged his young opponent to go for a review. Zverev called for one and it turned out that the serve had landed on the line indeed and resulted in Zverev winning the point.

Despite losing the point, the crowd gave Federer a huge round of applause for his display of incredible sportsmanship. Federer eventually lost the set and the match 6-7, 7-6, 6-7, but with this amazing gesture, he surely won the hearts of the crowd on the day.