Saints had enough chances in the final quarter of this poor-quality game to secure victory over visiting Vipers.
However, careless finishing left them ruing missed opportunities that would have kept them at the top of the table.
The showers throughout the afternoon were a mitigating factor but the overall quality of play was disappointing.
Vipers, once known for their running rugby, now rely on some hefty forwards and the powerful boot of their fly-half to accumulate points.
Saints showed more ambition with fewer opportunities but their execution was well below their usual standards.
Vipers went ahead after only two minutes with a penalty and they successfully played the territorial game to keep Saints pinned in their own half for long periods.
A quick break out produced a Ryan Taylor penalty but Vipers then put over two of their own as their forwards continually denied the home side any worthwhile possession.
A second Taylor penalty meant they trailed by just three at half-time having absorbed a lot of pressure.
A change of tactics from the kick-off paid immediate dividends as Vipers failed to deal with two towering kicks out of the low sun and conceded a penalty which tied the scores.
Unfortunately Saints offended at the restart and Vipers regained the lead.
With rain falling again the high kick option was lost but Saints began to play with more fluency and pushed the visitors back on the defensive.
A promising attack was halted but an offence at the breakdown produced a penalty in front of the posts.
To everyone’s amazement the prolific Taylor missed the kick but the reprieve was temporary.
The referee finally lost patience with Vipers persistent offences in the red zone and yellow carded their No.8.
Taylor duly obliged with this more difficult attempt and Saints went all out for the winning score.
A controlled driving maul was pulled down feet from Vipers’ line but the penalty try was not awarded and the scrum was given to the defenders.
The draw drops Saints down to third place.
If they want to be in the frame at the end of the season they need to eliminate basic errors and be more clinical in their finishing, starting this week with the trip to Rushden & Higham.
Saints 2nd lost their unbeaten record In Warwickshire Two going down 29-20 to a more experienced Pinley outfit.
Outgunned by the home side’s stronger and more streetwise pack, Saints struggled for possession throughout and tired in the second half.
Saints scored two good tries through Liam McKechnie and teenage fly-half Tom Oglethorpe. Ryan Sabin put over both conversions and two penalties.
Result: Midlands Three East (South)
Rugby St Andrews 12
Leicester Vipers 12