United Services threw away a winning position in their 34-33 defeat by unbeaten league-leaders Solent University at Burnaby Road.
With an hour gone, Services led 33-17 and looked on course to inflict a first defeat of the season on the students.
The visitors, however, finished stronger and snatched the win with a converted try deep into stoppage time.
‘It is hugely disappointing,’ said US director of rugby Simon Burns.
‘We gave away too many penalties in the second half and tried to play rugby in the wrong areas.
‘In the closing stages we defended well but just couldn’t keep them out at the death.’
The crucial score came when the home side had Paul Connor yellow carded and the students drove over from the quickly taken penalty.
Earlier, Services had fought back from 17-3 down to lead 20-17 at half-time.
Iuean Clements kicked two penalties and converted a Wayne John try.
The home side took charge at the start of the second half with two Chris Marriott tries.
Clements added the two conversions and kicked a brace of penalties.
Portsmouth crashed to a 30-8 defeat by London Cornish at Rugby Camp in London two south west.
The city club led 8-3 at the break but a poor second half saw the visitors score three tries without reply.
A long winter battling against relegation looks in store for new coaches Sid Street and Mike Hoban with their side propping up the table without a point.
In Hampshire two, Locks Heath Pumas went down 18-13 to unbeaten leaders Petersfield at Penns Place.
Pumas points came from an Andy Martin try with Nick Desefano adding two penalties and a conversion.
‘We can be proud of our performance and it shows that we can compete at this level,’ said Martin.
Fareham Heathens thrashed Stoneham 103-0.
The win moves Heathens up to second in the league, one place ahead of the Pumas, as they chase Petersfield.
Southsea Nomads returned from Aldershot & Fleet with a 27-17 win under their belts.