Chasing a modest target of 265, and with a batting order featuring Black Caps Hamish Rutherford, Jimmy Neesham and Mark Craig, as well as former test opener Aaron Redmond, the Volts should have cantered to victory.
But only Redmond (64) and Derek de Boorder (33) were able to make significant contributions as Otago slumped to be all out for 203.
''That was a really poor display from us and I know the boys are not proud of that performance and will be looking to right that over the next two or three games to make sure that does not cost us our No 1 or No 2 seed,'' Wells said.
Otago hosts Canterbury at the University Oval today and a win will guarantee the Volts a place in the playoffs. But Wells said the goal was to win the remaining three games and ''get a home semi and the two lives you get if you finish one or two''.
Otago was in third place at the start of the round with 13 points from five games. Wells has been a key contributor in what has mostly been a good campaign by the Volts so far. The 30-year-old has been given an extended run at the top of the order and has risen to the challenge.
When test opener Rutherford returned, it was expected Wells would drop down the order. But the captain Redmond made the sacrifice instead.
''I enjoy opening but it is not easy to get a chance to open when you've got a number here. But I was given a small chance and I've sort of grabbed it a bit.
''And it was a massive show of faith by the captain and the coach to keep me there ... so it is up to me to repay that faith and try to score more runs.
''I've scored a few but I've let two or three starts go when I should have got bigger scores. I've been in good form so I probably should have cashed in a bit more than I have.''
Wells is Otago's leading scorer with 212 runs at 42.44 and he has been in good form with the ball as well. He has taken nine wickets at 19.77 and the excellent economy rate of 4.52 - the fourth-best in the competition.
He is rather surprised with how the bowling has been going. Having picked up a calf injury during the twenty20 campaign, Wells had precious little bowling under his belt at the start of the one-day competition.
''It is fair to say I had not had a lot of bowling heading into that game in Alexandra. In fact that was my first bowl off my long run.
''I was a little bit surprised I got thrown the ball and luckily, it somehow came out all right.''
Wells took three for 15 in a record 222-run win but did not bowl his full allotment of 10 overs until round four.
Otago has made two changes from the side which lost to Wellington by 61 runs. Neesham has been sidelined with a back injury which is not thought to be too serious. James McMillan injured his calf at training on Monday and will be out for four to six weeks. Seamers Bradley Scott and Sam Blakely come in as replacements.
Canterbury has made one change, with Leo Carter replacing Black Cap Matt Henry.
Otago v Canterbury
Today, University Oval, 11am
Otago: Hamish Rutherford, Sam Wells, Michael Bracewell, Aaron Redmond, Derek de Boorder, Iain Robertson, Mark Craig, Josh Finnie, Neil Wagner, Jacob Duffy, Sam Blakely, Bradley Scott.
Canterbury: Henry Nicholls, Roneel Hira, Neil Broom, Peter Fulton, Brendon Diamanti, Andrew Ellis, Todd Astle, Freddie Anderson, Ryan McCone, Logan van Beek, Hamish Bennett, Leo Carter.
