Would May have scored having side stepped Claassens? Who knows - he wasn't given the chance.
The decision was placed in the hands of Televison Match Official Trevor Fisher, who advised referee David Rose to show the red card and award a penalty try.
Kingsholm duly erupted. Gloucester had used their get out of jail free card to take the four points.
In truth, had Gloucester lost, they'd have had only themselves to blame. They led for most of the game, dominated possession and territory but failed to put Worcester away.
In fact, both of Worcester's tries were courtesy of lapses in focus on the part of the Cherry and Whites. The first a breakdown in defence, the second an interception.
It meant that Worcester were clinging to a 23-22 lead, with time up on the clock and Gloucester desperately seeking a score from anywhere.
Credit to Gloucester, they didn't give it up. The never say die attitude that has characterised this season was there again and they launched one last attack from deep.
May screamed down the left hand touchline, stepped inside Claassens and the full back stuck out his leg to trip him. The rest is history.
Worcester followers will feel aggrieved. They felt similarly up at Sixways earlier this season, when Freddie Burns kicked a last minute penalty to snatch a draw.
Gloucester will simply breathe a sigh of relief as their top four ambitions remain alive.
A tough week, Gloucester faced a five day turnaround, got worse when the team was hit by the late withdrawal of Mike Tindall who didn't make it through the warm up. Tim Molenaar started alongside Henry Trinder in the centre.
The Warriors had the first chance of points. Gloucester were penalised at an early ruck, but Andy Goode's long range penalty struck the crossbar and bounced clear.
Rob Cook, however, made no such mistake when presented with a similar opportunity a few minutes later and gave Gloucester a 3-0 lead.
Cook's searing break from his own half as Gloucester countered from deep, then led to a second penalty chance as Worcester killed the ball, and the full back made no mistake.
It was a good start from the Cherry and Whites, and could have been even better had Jonny May managed to latch on to a lovely grubber kick from Henry Trinder but the ball just ran dead.
The visitors were also looking lively though, and took full advantage when Gloucester kicked possession away cheaply, Goode slotting the penalty with ease.
Gloucester seemed to have a clear game plan at this point, to use the pack to punch holes around the breakdown. It was effective and led to another penalty chance, but Cook dragged his kick wide left.
Neither side was really at this point, but a great break from Tim Molenaar had the Warriors defence at sixes and sevens. Sione Kalamafoni couldn't quite make the line though as a defender hung despairingly to his foot.
Sam Betty was sinbinned for tackling without the arms in the build up, so Gloucester twice went for the catch and drive, but knocked on right on the Warriors line and the visitors survived.
It was a big moment, and even bigger as the Warriors moved downfield. Josh Matavesi evaded an onrushing Henry Trinder in midfield, stepped Darren Dawidiuk and scored behind the posts. Goode converted to the delight of the travelling fans.
It was a sucker punch but, crucially, Gloucester his straight back. Cook spotted space out wide and put Jonny May in the clear. The winger made good ground, before finding the supporting Henry Trinder who sprinted home. Cook converted to restore the lead at 13-10.
Even then, the action wasn't quite done. With Goode hobbling, Chris Pennell tried a penalty from inside his own half but was short and wide.
Having dominated for so long, the Matavesi try could have knocked the stuffing out of Nigel Davies' side, but they responded well. The challenge would was not to make much more of any scoring chances in the second half.
The first came quickly. Worcester held on in the tackle in front of their own posts straight from the restart, and Cook kicked an easy penalty.
Gloucester were then gifted another shot at the posts, when a Warrior took a man out late and Ryan Mills landed the long range attempt for 19-10, only for Andy Goode to immediately respond in kind to keep his team in touch.
The game was still in the balance at this stage. Neither team could quite gain the upper hand, and Gloucester were indebted to a couple of key turnovers at the ruck area to ease some pressure.
The Warriors then, inexplicably wasted a chance to make it a three point game, when they turned down a kickable penalty in favour of a kick out wide which ran dead.
However, Gloucester committed suicide after Goode missed a 60th minute penalty.
They took a quick drop out and started to play Barbarian style rugby on their own 22, only for Alex Grove to intercept and score. Goode's conversion made it 20-19 to Worcester.
With the clock against Gloucester, it was a time for cool heads. Huia Edmonds had added a spark after his introduction, and he was prominent as Gloucester remained patient and carved out a 70th minute penalty chance, which Cook slotted.
Ten minutes remained, but there was still time for plenty of drama.
Dario Chistolini replaced Rupert Harden, but then aggravated an injury and was gone after one scrum. Harden returned but was penalised for not rolling away and Danny Gray put Worcester back in front with the penalty.
The tension mounted as Gloucester fought so hard to get into Worcester territory and try and eke out a penalty.
Time ticked away and it looked as though this one was going to slip away and leave a bitter taste in the mouth.
Cue the dramatic last few seconds which will be spoken about in depth on the respective supporters' message boards.
|Gloucester Rugby Score Card|
|Worcester Warriors Score Card|