In fact, as the game headed for its final stages, the Tigers looked the more likely winners as they played the game in the Gloucester half with the home side struggling to move downfield.
However, a critical late turnover gave Gloucester a territorial foothold and some committed late running opened up a gap for the Volcano and he needed no second invitation to plunge over in the corner and secure the points.
Kingsholm erupted in joy as Robinson's touchline conversion provided the icing on the cake before he hoofed the ball off the park from the restart to end the game.
There's no doubt that the platform was laid by Gloucester's pack who operated at full capacity. But it was equally as heartening to see young bucks such as Trinder and May coming of age in the cauldron of this Aviva Premiership encounter.
It was a tribute to both sides to deliver such a pulsating spectacle given that two finely oiled machines were denied some key cogs due to international call ups and rugby was the real winner on the night.
A vociferous and highly charged Kingsholm crowd were behind Gloucester from the off and were given early encouragement by Charlie Sharple's salmon like leap to claim a high cross kick.
But it was Leicester who had the first chance of points as Gloucester conceded a couple of cheap penalties. Billy Twelvetrees was wide out on the left, and in front of the Shed, and coolly slotted the penalty for a 3-0 lead.
Brett Deacon enjoyed an early rumble against his former team after a great offload from Luke Narraway as Gloucester looked to hit back but had to receive lengthy treatment after taking a heavy tackle and was eventually replaced by Peter Buxton to bring a sad early end to his afternoon.
Henry Trinder's smart kick through then pinned the Tigers back near their own line and the visitors lineout misfired. Gloucester forced a penalty from the 5m scrum and Robinson levelled the scores.
The Tigers were straight back on the attack though as Gloucester failed to gather the restart. Alesana Tuilagi took some bringing down and Gloucester were caught offside in midfield giving Twelvetrees an easy penalty for 6-3.
The visitors were looking dangerous and it took a try saving tackle from Jonny May to deny Anthony Allen before a turnover had Charlie Sharples kicking ahead into the Leicester 22 only for Scott Hamilton to get back and clear the danger.
A long period of Gloucester pressure followed the Tigers defence was showing no signs of weakness at this stage as Cherry and White constantly hammered into Green, Red and White.
Gloucester finally got a break on 20 minutes as Andy Hazell charged down Twelvetrees' kick from his own in goal area to force a 5m scrum. Again, Gloucester won a penalty and again Robinson made the scores level.
The game entered an attritional phase with neither side able to get an upper hand with an off target penalty from Robinson from halfway the only scoring chance.
A powerful surge from Luke Narraway almost opened up the Tigers as James Simpson-Daniel just failed to scoop up a grubber kick off his toes and play came back for a difficult penalty which Robinson pulled wide.
The Kingsholm crowd were getting into it as superb Gloucester defence forced another penalty. Again, it was wide out and from distance but Robinson bisected the posts superbly for 9-6 after 35 minutes.
Gloucester needed to make it into half time intact but had a couple of real scares as Rory Lawson had a kick charged down forcing Robinson to cover superbly before Lawson made amends with a timely intercept of what looked to be a scoring Tigers pass.
The alarm bells had rung loud in a frantic last couple of minutes but Bryan Redpath's side made it into half time with their noses in front.
It had been passionate, committed rugby at a ground fizzing with atmosphere under the Kingsholm floodlights with both sides at it hammer and tongs.
Both sides had created half chances but there were two excellent defences on display and the feeling was that it may turn out to be a kicking duel. Gloucester had already missed two - would it matter in the final outcome?
Gloucester took the field to rapturous acclaim and the Shed were in full voice as the pack forced three penalties in a row to give Robinson another tough penalty opportunity but the Welsh fly half was just wide with his attempt.
A superb steal at a Leicester ruck by Narraway moving forward again and Leicester had to concede yet another penalty as they scrambled back to cover Robinson's grubber kick. Robinson made no mistake off the kicking tee and made it 12-6.
A furious response followed from the visitors and, although Simpson-Daniel dealt smartly with a dangerous kick through, Gloucester came in at the side and Twelvetrees nailed the penalty for 12-9 after 51 minutes.
The tension was rising and Gloucester were still getting little change out of a dogged Tigers defence. The visitors, for their part, were being let down by rare handling errors as they looked to get back on terms.
A mental aberration by number eight Thomas Waldron then hurt the Tigers as he opted for a quick tap penalty bang in front of the Gloucester posts only to be turned over. Kingsholm held its breath…
The Tigers started to turn the screw and forced Gloucester back with some intelligent kicking. Eventually, Gloucester transgressed and Twelvetrees made it 12 all after 64 minutes.
At this stage, it was all about playing the game in the right areas of the pitch and, at this point, the Tigers were getting it right.
However, a Tigers error in their own half gave possession to Gloucester as Vainikolo scooped up the loose ball and the home side poured through. Leicester killed the ball near their own line and Matt Smith was yellow carded but Robinson missed the kick.
It looked as though Gloucester's last chance had gone but this Gloucester vintage has some real fight to it and a frenetic late attack saw just enough space created for the key try from Vainikolo.
The heavens opened as the celebrations began and the realisation dawned that Bryan Redpath's side now move into third place in the table.
|Gloucester Rugby Score Card|
|Leicester Tigers Score Card|