It's the Ospreys versus Cardiff this week and that's a fixture which has produced its fair share of feisty moments over the years.

There have been countless cards of varying colours handed out along the way and plenty of controversy, while some of the incidents are the stuff of Welsh derby folklore.

So, ahead of Saturday evening's United Rugby Championship clash in Swansea, here are the stories of some of the most infamous encounters from the early years of regional rugby, along with some more recent high-octane encounters.

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Martyn loses it (part I)

January 2005: Cardiff Blues 9, Ospreys 15 (Arms Park)

You couldn't meet a nicer bloke in rugby than Martyn Williams, but when the Ospreys were in town there was a tendency for the red mist to descend.

First off, there was a league game at the Arms Park on New Year's Day in 2005 when his attention turned to a certain Gavin Henson.

Double Grand Slam winner recounts the tale in his autobiography, My Grand Slam Year.

"Martyn seemed to be in a daze that afternoon, as if he'd gone into his own little world.

"I put a big tackle in on the Cardiff scrum-half Ryan Powell. At the next ruck, I cleared out a couple of players and fell to the groun.

“All of a sudden Martyn came flying in on top of me and started throwing punches.

“He was screaming too. ‘You don’t like it in the face do you, pretty boy! You can’t handle it’.

“I managed to grab him and turn him onto his back and then some other players came in to break us apart.

“'What’s your problem?’ I said to him but his eyes had glazed over. Mentally he was somewhere else. He was just staring into space."

So what did Williams make of what Henson wrote?

"I couldn't really have any complaints about it, because all of it was true!" he said in his own book 'The Magnificent Seven'.

"I thought to myself 'Who is this Flash Harry? Who does he think he is?' and I kind of lost it with him.

"Emotions were running high, as they often do in Welsh derbies, and I guess I got caught up in the moment."

It was the Ospreys who came out on top on the day, thanks to tries from flanker Richie Pugh and scrum-half Jason Spice.

Martyn loses it (part II)

December 2006: Cardiff Blues 30, Ospreys 24 (Arms Park)

Speaking of Spice, he was at the centre of another flare-up involving flanker Williams at the Arms Park a year later.

Martyn was red carded for butting the Kiwi No 9, the one and only time he was sent off during his illustrious career.

Afterwards, he issued an apology, saying he was disappointed with his reaction and that he regretted the incident which saw him banned for three weeks.

Speaking about it recently, he said: "They'd won a penalty and I had the ball in my hands. So I turned to walk away with the ball, just to stop the quick penalty.

"Jason obviously wanted to get the ball so he ran up behind and gave me a bit of a clip behind the ear and I lost it.

"It was probably a bit of a footballer's headbutt! It was my one and only red.

"Thankfully, we still won that day."

Indeed they did, with full-back Ben Blair scoring 25 points, including two tries.

Martyn Williams is sent off against the Ospreys in 2006

By God, he disliked me!

March 2007: Ospreys 27, Cardiff 10 (Millennium Stadium)

Probably the best remembered and most infamous dust-up of the lot.

Going into the EDF Energy Cup semi-final, all the focus had been on the two opposing scrum-halves - Mike Phillips and Justin Marshall.

Phillips was to leave Cardiff to join the Ospreys at the end of the season, so they were going to be rivals for the No 9 jersey.

The scene was set and it was to be an explosive showdown, as the friction between the pair boiled to the surface.

It was All Blacks great Marshall who came out on top on the pitch, being named Man of the Match on an afternoon when the Blues had three players yellow carded.

But it was off the pitch that things really kicked off, as the two scrum-halves were involved in an altercation in the tunnel.

Recalling the incident on the Scrum V podcast last year, Marshall said: “He grabbed me by the throat after the game when I tried to shake his hand.

“That’s how wound up he was. He was angry."

He revealed he had first crossed swords with Phillips two years earlier while playing for Leeds against Cardiff.

“By God he disliked me," he said.

"That was very evident 20 minutes into the game. I was not a favourite of his.

"A lot of it was really personal.‘You’re rubbish. What are you doing out here?’ Blah, blah, blah.

"At this stage, I’d played 81 tests for the All Blacks so I thought I was okay!

"But I was no good in his mind. It was quite a ferocious approach."

Marshall claims there was a further frosty encounter off the pitch ahead of their 2007 Millennium Stadium showdown.

"What he did that annoyed me was that he approached me one night in a pub in Swansea and had another go, with the same sort of stuff. 'You're rubbish. I'm a better player than you and all that'.

"That's stepping out of the boundaries and you probably deserve to be pulled in a little bit."

On the game itself, Marshall said: "We had a good day. We played pretty well and got on top early and I was just reminding him he was signing a very big contract to come and sit on the bench behind a 34-year old."

So what about Phillips' take on it all?

“The way I looked at it was: He’s Justin Marshall, he’s got 80 caps, he’s been one of the best in the world and I’m going to try and beat him. I want to be the best in the world.

“He’s arguably one of the best that’s played the game and you want to push yourself to be as good as you can be.

“Me giving stick to people on the field was always about me, it wasn’t about anybody else.

“It was to spark that competitiveness in me or maybe, at times, I was a bit nervous or edgy.

“It was never personal with anyone. You just want to win so much you use anything you can.”

Justin Marshall tackles Mike Phillips during their 2007 showdown

As for how they got on as Ospreys team-mates, Phillips said: “I didn’t really speak to him that often but what I did see was that he was an absolute winner, a competitor.

“He wanted to start every game.

“I remember I got picked against Gloucester in the Heineken Cup. As soon as it was announced, he threw his toys out of the pram a little bit and that surprised me.

“But the era that he came through was dog eat dog and that’s what made him so good."

The other niggles

December 2010: Cardiff Blues 27, Ospreys 25 (Cardiff City Stadium)

A crowd of 22,160 watched this New Year's Eve showdown, which proved to be a typically feisty derby.

The Ospreys were unhappy that prop Paul James was sin-binned early in the second half, along with his opposite number, Taufa'ao Filise, following a scrum collapse, as they felt the Tongan had spent the game boring in.

Ospreys forwards coach Jonathan Humphreys said: "It is about time officials consulted with scrum coaches about what goes on up front. There are some big issues here."

It was the 14 points from the boot of Blues fly-half Dan Parks that proved decisive in the end.

November 2016: Cardiff Blues 7, Ospreys 31 (Arms Park)

Georgian prop Anton Peikrishvili was sent off for biting Ospreys back-rower Rob McCusker on his first start for the Blues in this Anglo-Welsh Cup tie.

After being involved in an altercation on the deck, he was pulled to one side by referee Ben Whitehouse and given his marching orders. Peikrishvili was banned for six weeks.

December 2019: Ospreys 16, Cardiff Blues 19 (Liberty Stadium)

The visitors had three players yellow-carded during this PRO14 clash, with Filo Paulo, Tomos Williams and Josh Adams all being sin-binned.

But they still pulled through to claim their first league win in Swansea since 2005, with Jarrod Evans crossing for a crucial try and a late penalty from fellow fly-half Jason Tovey sealing the victory.

January 2021: Cardiff Blues 3, Ospreys 17 (Cardiff City Stadium)

The most recent league meeting between the two sides was another encounter where disciplinary issues took centre stage.

Referee Ben Whitehouse handed out four yellow cards, three of them to Blues forwards, with the hosts paying for their indiscretions.

The sin-binning of Ospreys flanker Dan Lydiate for leading with an elbow as he carried into Jason Tovey sparked much debate and polarised opinion.

Some argued he should have been sent off for making contact with Tovey's throat. Others pointed to Tovey's high tackle technique, while some felt a yellow was the correct decision on balance.

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