Monaco's Vacherot, who is not used to playing at this level, had made the long journey into the main event by winning two matches in the qualifying tournament.
Since then, Vacherot surprisingly defeated the world no. 17, 23, and 31, who were all seeded in the tournament, en route to the quarter-finals.
However, from the start of the match, Rune took control of the game and dominated duels from the back line. Rune, who, like Vacherot, is a resident of Monaco, produced several winners and succeeded in forcing an early break after a long game to take a 2-1 lead.
Vacherot was far from outplayed, but Rune's experience gave him the edge to serve home the first set 6-2.
However, Vacherot never allowed the first set loss to mentally affect him, and he showed great strength in breaking Rune's serve to take a 3-1 lead in the second set.
However, Rune, who earlier in the set had missed a few break points, immediately broke back to 2-3 and restored parity shortly after to make it 3-3. Vacherot still fought for every ball, and every time Rune became too passive, the opponent pounced.
Rune had to find his best game to stay in the second set and equalized at both 5-5 and 6-6. Thus, it had to be decided in a tiebreak, and it was as close as the rest of the set.
While Vacherot produced big winners, Rune's errors crept into the game, and it cost him the set. In the third set, Rune seemed to struggle with heavy legs. Treatment against cramps between the games did not help much, and Rune was broken cleanly at 3-3.
Rune had several discussions with his coach and others in the VIP box, and his mother, Aneke Rune, left the arena. Down 3-4, Rune attempted a comeback, but the cramps became pronounced, which prevented the Dane from running.
At 4-5, Rune had two break points to break back, but the Monegasque, who did not seem physically inhibited, kept his composure, averted the break points, and a late Danish comeback.