The Welshman, who finished third in Thursday’s time trial as well as the Commonwealth Games points race in 2006, broke clear from a three-man group eight kilometres from the line and stayed clear to take the gold medal.
Thomas’s attack on the main climb of the day saw him immediately ride clear of his companions Jack Bauer (NZl) and Scott Thwaites (Eng). His advantage was steadily climbing as Bauer and Thwaites knew they couldn’t match the Welshman’s speed.
But then, disaster. Thomas’s front wheel punctured – his second of the race – and he got an agonisingly slow change, seeing him lose around 30 seconds with just six kilometres remaining. Luckily his advantage was such that he remained out of sight of his chasers.
It was an impressive display by the Welshman, who showed little sign of Tour de France fatigue on the challenging city centre circuit. The inclement weather throughout would have only contributed to the difficulty of this 168-kilometre affair.
While Thomas was happy to wait, the highly-tipped Peter Kennaugh attacked within the first three kilometres.
Kennaugh, who took silver in the points race last Saturday, made light of the conditions and had been clear for 95 kilometres and held a 1-50 lead before any reaction came from the remnants of the peloton.
Australian Nathan Haas, who had been sharing his team’s workload with Caleb Ewan and Michael Hepburn in an attempt to set Mark Renshaw up for a sprint victory, accelerated through the finish line at the end of the seventh (of 12) laps.
But Haas’ attempts to bridge lasted half a lap, as Kiwi Shane Archbold picked up the pace-setting.
That reduced Kennaugh’s gap to 1-15 after eight of the 12 laps, and when Archbold’s team-mate Jack Bauer attacked early on lap nine, the nature of the race changed significantly.
Thwaites (England) and Thomas (Wales) followed Bauer – who recently came within metres of winning a Tour de France stage after a day-long break – and they caught Kennaugh with 49 kilometres remaining. The Manxman had spent 116km clear on his own, and quickly lost contract with the trio.
This is where Australia’s day deteriorated. Renshaw punctured, and the attempts of rising star Ewan to bridge to the leading trio failed. He got to within 20 seconds of them, before he was caught by six chasers. Renshaw required a bike change, too, with 28km to go and Ewan slipped out the back of the small group.
By now, the leading trio were over two-and-a-half minutes clear, so there was little chance of anybody else taking a medal.
Bauer, Thomas and Thwaites rode coherently until the final the final ascent of St Vincent Street. The Welshman attacked at the bottom of the incline, and immediately got a sizeable gap.
From there, he replicated what Lizzie Armitstead did in this morning’s women’s event and soloed to the victory – albeit with a significant scare when he required a wheel change at Park Circus.
2014 Commonwealth Games men’s road race 168.2km
1. Geraint Thomas (Wales) 4:13:05hrs
2. Jack Bauer (New Zealand) +1:21
3. Scott Thwaites (England) +1:21
4. Russell Downing (England) +4:29
5. Mark Renshaw (Australia) +4:29
6. Luke Rowe (Wales) +4:32
7. Greg Henderson (New Zealand) +5:15
8. Peter Kennaugh (Isle of Man) +5:15
9. Dan Craven (Namibia) +9:03
10. Scott Davies (Wales) +10:10