The Bournemouth Lions' charge for a bonus point was cut short three minutes early by the referee as Shelford came away from Chapel Gate with a 24-10 win.
Some bizarre refereeing overshadowed a brave display from the Lions as the Dorset side fell to their fourth straight defeat.
Referee Michael Cooper ended the clash at Chapel Gate three minutes early, with the Lions pushing for a try that could have given them a much-needed extra point.
The Lions got off to a sluggish start and handed the visitors an early lead. Despite dominating the second half - Bournemouth couldn't create enough momentum to complete a comeback.
Bournemouth had a mountain to climb and it proved to be too much as the visitors claimed a 24-10 win thanks to four tries.
The Dorset side were not helped by some inconsistent refereeing - which culminated in Mr Cooper blowing the final whistle after 77 minutes. Although the contest was as good as over with the Lions trailing by 14 points, a converted try would have handed Bournemouth a vital losing bonus point.
Lions Director of Rugby David Dunn said: "I'm very proud of a lot of good things. I thought there were a lot of positives to take out of that performance. It's just a shame that we gave them a 12-point lead. But after that, I thought it was a really good game of rugby.
"We won the second half. I think I'll get a lot of support for saying that decisions didn't go our way today, which was so disappointing.
"It's just beyond a joke when the officials can't even manage the time. But we must not focus on that, we must focus on ourselves. I was very proud of the forward pack. I thought we used the ball much more effectively."
The away side wasted little time to get on the board as Dane Grey grabbed a try after 80 seconds - taking advantage of a strong forward push.
Five minutes later, Bournemouth were facing an uphill struggle when a fantastic passing move down the wing was finished off by Charlie Baker. Steve Smith's conversion gave Shelford a 12-point lead inside the first ten minutes.
The hosts applied more pressure up front, and managed to break the Shelford line through Scott Chislett. However, his long pass towards Paul O'Brien was too big an ask - and the promising move broke down.
The Lions found it hard to play their passing rugby in the first half, but finaly got on the board after 25 minutes through Ben Stevenson's reliable boot.
The revival didn't last long however, as two quick yellow cards stopped any Bournemouth momentum - as they were harshly penalised for infringements.
To the Lions' credit, the numerical disadvantage didn't stop their ambitions. A quick penalty by Sam Hardcastle nearly ended in Bournemouth's first try. However, possession was given away cheaply, and Shelford broke quickly with Nigel Conroy driving over to give the visitors a 19-3 lead at the break.
Bournemouth gritted their teeth at the start of the second period, as they took the game to Shelford. The Lions dominated much of the half, but were frustrated as line-out and scrum infringements were harshly penalised.
The Lions finally got a deserved try when Chislett found a way through the solid Shelford line. Stevenson added the extra points to cut the deficit to 11 points.
However, before Bournemouth could think about launching a comeback, Shelford scored a drive-over try to put an end to any recovery from the Lions. The try proved controversial as Alex Manning claimed to have his hand under the ball, meaning the ball may not have been grounded for a try.
With the Lions still pushing to seal a losing bonus point, a quick break down the wing was cut short for a line-out with three minutes remaining. Despite the clock on full display, Mr Cooper blew the final whistle - much to the amazement of the players and fans.
The Lions created enough chances to win the game, but unforced errors and some unfortuante decisions proved that National League Two South can be an unforgiving league.
"It's work in progress" added Dunn. "Playing up at this level is a big step up, playing against sides who have been here a long time, palying against sides who have got much more professional resources - and it makes a huge difference at this level.
"It's that learning curve which is the most important thing. We must stay positive. We've got another hard trip next week to Henley. But after that game then we're playing against the teams that are beneath us in the league - and that's where we have to pick up the points."