In his opening two matches of the World Championships, the planet's best snooker player found himself coasting through matches in about third gear.
Reigning champion produces incredible session of snooker
Even in Tuesday's opening session Mark Selby did not really show his true quality but established a 6-2 overnight lead against an out of sorts Marco Fu. Hong Kong's finest had previously produced two miraculous comebacks to reach the last eight but his luck was about to run out.
A break of 78 to begin the second session was a light warm-up to the drama that was about to unfold. After edging another frame, Selby took a 9-2 lead after a re-rack in frame eleven preceded a break of 52 from the World champion.
Then the fireworks really began. Selby set the fourth highest break of the tournament at that stage with an excellent 132, only to trump it with a 139 to put him to the top of the leaderboard in those standings. Even when Fu managed to register a frame, his half-century contribution was outscored by a 57 from Selby.
Frame fifteen was a moment to remember for those lucky enough to be present at the Crucible. Selby produced a quite remarkable 143 in a third total clearance of the session, leaving snooker legend Stephen Hendry purring "that is one of the best century breaks I have ever seen". Selby then wrapped up the contest with a session to spare as a break of 65 saw him over the line with a mouth-watering pot success rate of 95%.
Higgins back in the final four
John Higgins also progressed to the final four and wasted little time in seeing off Kyren Wilson. Leading 11-5 overnight, the four-time World Champion scored 61 to put himself within a frame of victory. Wilson pulled a frame back, only for Higgins to return to the semi-finals for the first time in six years after a break of 59 secured his place.
Higgins now awaits the winner of Barry Hawkins against Stephen Maguire with his fellow Scotsman 5-3 behind. Meanwhile, the imperious Selby will be looking forward to the winner of Ding Junhui against Ronnie O'Sullivan with the man from China holding a 10-6 advantage.