In fact the win, which now gives them a five-point cushion over sixth-placed Northampton, was the only win for a home team on Sunday.
Their enhanced position on the standings is probably the only positive the London side will take from a game in which their form was somewhat patchy.
Like all the other Zurich Premiership clashes on Sunday the team that opened the scoring – in this match Northampton opened with a Paul Grayson penalty in the third minute – ended up losing the match.
Alex King levelled the scores with a sixth minute penalty, before Grayson put his team ahead again a minute later.
The only other scoring in the first half was Leota's close-range try and the conversion by King – to make it 10-6 at the break.
King added a 42nd minute penalty (13-6) and Grayson gave his side some hope with a penalty in the 57th minute, before King sealed it with a drop-goal at the death.
For London Wasps: Try by Trevor Leota. Alex King kicked one conversion, two penalties and a drop-goal.
For Northampton Saints: Paul Grayson kicked three penalties.