When the third man in the ring does his job well, the spectator shouldn't even really know they're there - they should be making sure nothing dirty happens, and facilitating the flow of the fight.  Here are a few prime examples of where the referee wasn't doing their job. And please - feel free to add your own in the comments.  There are so many of these out there that I'm not mentioning that are poorly done for so many different reasons (e.g., every Laurence Cole fight, Joe Cortez not letting Ricky Hatton fight on the inside, etc.) that I can't possibly name all of them.  And I know there were a few old, old fights that I just don't know well with all kinds of horrible things happening, especially in the old Vegas fights where local politicians and mob bosses with no experience were often the referees.

Juan Martin Coggi vs. Eder Gonzales - This fight had one of the strangest sequences ever.  Coggi knocked down Gonzales and appeared to be cruising on his way to victory.  As Coggi backed Gonzzales into the ropes, Gonzales came back with a HUGE right hook over the top, knocking Coggi down like a tree.  Coggi didn't get up until about 15, and even then, he was bouncing off the ropes like a pinball.  Gonzales was then knocking the snot out of Coggi in the corner, when the referee inexplicably broke them up and didn't give Coggi a count.  At that point, Coggi still couldn't stand, but the referee didn't intervene.  The referee then hugs Coggi, as if the fight is over, and Gonzales starts celebrating that he just won the championship, but the fight isn't over!  Then Coggi's corner gets up on the ring apron, which should have been an automatic disqualification (notwithstanding the fact that Coggi had already been knocked out twice), the time stopped for about 30 seconds for Coggi to recover, and the fight continued.

Arthur Abraham vs. Edison Miranda I - Here's another example of home field advantage, and poor refereeing led to a rematch.  Edison Miranda was deducted a total of five points in this fight, two of them on ticky tacky calls, but that's not the big part.  In the fourth round, Miranda broke Abraham's jaw.  Abraham, tough guy that he is, fought on with the fairly gruesome injury, and continued to come forward.  In the fifth round, Miranda nailed Abraham with an unintentional headbutt.  It was a legitimate butt, but didn't really buzz Abraham.  Despite this, the referee Randy Neumann gave Abraham the full five minutes to recover, all the while letting both the doctors and his corner come up on the apron to treat Abraham's broken jaw.  At that point, there were really three legitimate options - Abraham DQ because his corner was on the apron during a round, doctor's stoppage because Abraham was unable to continue, or the doctor checks out the injury, lets Abraham continue and the fight moves on without serious recovery time.  Instead, none of those things happened, and Abraham was given lots of time to recover and the fight continued.  Abraham won by controversial decision, in part because of the deductions, but then cleared things up in a rematch, knocking out Miranda in 4.

Julio Cesar Chavez vs. Meldrick Taylor I - This was actually a well-refereed fight, but the ending is too controversial not to be mentioned here. Taylor was beating Chavez pretty soundly in the fight, although Chavez had been beating Taylor up to the body all night.  Taylor's corner gave him some all-time stupid advice before the 12th, telling him he needed the knockout.  Rather than playing safety first and cruising to a decision victory, Taylor came out, guns blazing, and got in a firefight.  In the last 30 seconds, knowing he needed a knockout, Chavez went whole hog, wailing with bombs and eventually backing Taylor into a corner, knocking him down with 16 seconds left to go.  Taylor got up by the count of 7, but didn't take a step forward or lift his gloves.  Referee Richard Steele looked in his eyes, and later said he saw a glassy look like Taylor didn't know where he was.  With 4 seconds left and Taylor otherwise ensured of a victory, Steele waved off the fight, giving Chavez the KO victory.  Taylor was never the same after that fight.  While he was the better fighter in the ring that night, he took a ton of damage, enough to effectively end his career as a top fighter.

Sven Ottke vs. Robin Reid - The referee probably snatched victory away from Reid this night, ensuring that Ottke could keep his VERY questionable undefeated record.  First, Reid very clearly knocked down Ottke with a hard right to the head.  The referee called it not a knockdown, and the fight continued. Then the referee kept warning Reid for leading with his head, when it was Ottke who was pulling Reid into headlocks.  Then, the referee actually deducted a point from Reid for - landing a punch!  He said the deduction was for a headbutt, but there was no butt, only two right hands that landed.  Reid ended up losing by two points.

Danny Williams vs. Konstantin Airich - This was just one of the strangest fights out there, period.  The referee deducted points when there was no foul.  The referee called no knockdown when there was a knockdown.  The referee called knockdowns when there was no knockdown.  The referee complained to the fighters that they were actually throwing too many punches.  One of the rounds got shortened by over a minute because the promoter rang the bell when his fighter was in trouble.  Despite the referee doing everything in his power to ensure an Airich victory, Williams was able to score the knockout.  Here's Scott's full post on this one, which goes into all the shenanigans in detail.

Lucian Bute vs. Librado Angrade I - A bad job refereeing, but in my opinion, the right call.  You already know this one, but here's the video:

Sergio Martinez vs. Kermit Cintron -This 'draw' was one of the worse robberies in history.  Martinez knocked down Cintron with a big right hand.  The referee counted to ten while Cintron was on the ground, but Cintron got up before the referee waved off the fight.  Still, the rules say that at the count of ten, the fight is over.  Cintron then proceeded to complain to the referee that he was knocked down by a headbutt (on replay, it was clearly a punch, and a very good one at that).  The fight continued, even though the referee made it to 10.  In the end, Martinez only made it out with a draw in a fight where he clearly won at least 8 rounds and scored a knockdown.  One of the only fights I can think of where the fighter was robbed by both the referee and the judges at the end of the fight.

Feel free to add some of your own in the comments, especially with respect to older fights.  It just seems like there's been a lot of very questionable refereeing lately, but I'm sure this is nothing new.