Along with Hildreth, the wicketkeeper put on 61 runs to help team to a last-ball victory and by four wickets.
Rush-job Snell delivers for Somerset in Champions League
Steve Snell, the replacement choice for wicketkeeper at Somerset, joined in a match-winning partnership with James Hildreth to take his team over the line in their first game of the Champions League qualifying yesterday.
Snell was commentating on club matches in England when he was approached because the two regular wicketkeepers for Somerset were called up for international duty.
He responded with an unbeaten 34 along with Hildreth (34) as Somerset won by four wickets and on the last ball of the innings.
Needing 126 to win, Somerset were 64 for five after a collapse in the middle overs.
The sixth wicket pair then put on 61 runs.
With 20 required off the last two overs, Hildreth and Snell hit some lusty blows to ensure a second defeat in as many days for Auckland. Lou Vincent was among the runs for the losing side again, top-scoring with 47 runs, after Monday's loss to Kolkata Knight Riders.
Earlier, Leicestershire slumped to a heavy defeat in their first game of the tournament qualifier as they lost by 51 runs to Trinidad & Tobago.
The Foxes never looked capable of chasing down their target of 169 after losing Andrew McDonald, the opener, for a duck in the first over.
They soon slumped to 20 for five after the fall of Paul Nixon, playing in his final tournament before retirement.
James Taylor, who remained unbeaten on 56, avoided a complete wipeout as Ravi Rampaul finished with figures of four for 14 in their four overs.
In contrast, the West Indies side had cruised to 168 for two, with Lendl Simmons making 67 off 58 balls and Adrian Barath adding an even more explosive 62 off 47, hitting six fours and two sixes.