"Has anyone ever scored with a rabona - crossing the right leg behind the left to strike the ball - in top-flight football?" asks Keith Kent.

First thing's first, here's our definition of the rabona, revealing the trick not to be leg specific as Keith suggests. It is widely understood to have been invented by Ascoli striker Giovanni Roccotelli, 'il padre della rabona' (the father of the rabona). "In every game the fans begged me to do it, they expected it," recalled Roccotelli when interviewed several years ago. "For me it was a natural thing. I began crossing like this when I was very little. When I was called up for a national side by [Enzo] Bearzot I remember that I even scored two goals this way in Campania. At least I did one thing before all the others ... now they call this move 'rabona' because Ronaldo did it, but Pele himself said in an interview that he remembered an Italian doing it before him: that was me."

Many readers suggested a host of goals as potential contenders, but skilful as they were, Gianfranco Zola's strike for Chelsea against Ipswich, Kanu's for Arsenal against Middlesbrough, Lee Sharpe's for Manchester United against Barcelona, and Rabah Madjer's for Porto in the 1987 Champions League final simply do not qualify as rabonas. Daniel Buse, however, presents one that does. "Dutch player Dave de Jong scored a rabona goal for VfL Osnabrück (third division) against SpVgg Greuther Fürth (second division) in a German Cup match in August 2005," he writes. And don't just take Daniel's word for it, not when you have this brilliant YouTube footage as evidence.

And while the defensive-minded Knowledge wonders why the Greuther Fürth defender vacated his post before the corner had been fully cleared, here's Felipe Patiño Arenas to introduce Andres Perez: "He is from Colombia, and during a friendly match in the Argentinian league, playing for San Lorenzo against Independiente, he scored this goal."

Also worthy of note is this agonising near-miss by Pablo Aimar, which surely would have been the best yet. If it had gone in. And if he really meant it.

'YOU'RE SUPPOSED TO BE ON THE SAME SIDE'

"Following Lee Carsley's accidental clash with Tim Cahill's knee, what other cases are there of players injuring a team-mate during a game?" enquires Sam Read.

As if in direct response to Sam's question, last Saturday's League Two clash between Stockport and Macclesfield served up one of the worst collisions between team-mates in recent memory. The Macclesfield goalkeeper Jonathan Brain and centre-back Andrew Teague were each ruled out for the season when, with 15 minutes to go, they collided as Teague chased a ball back into the area. Both suffered a broken leg in the incident, which, literally adding insult to injury, also allowed Stockport striker Adam Proudlock to steal in and net an equalising goal - hence denying the Silkmen their first win of the season.

A remarkably similar scenario in Australia's A-League earlier this year may yet force Perth Glory goalie Jason Petkovic into premature retirement after he ran into Simon Colosimo, snapping his tibia in the process. Colosimo also suffered a hamstring strain in the collision, and, according to Ben Godwin, "the additional twist is that the third player involved was the well-travelled Damien Mori - Petkovic's 'real-life' best mate and godfather to his kids."

Moving back in time for a few higher profile examples, Everton and Arsenal legend Joe Mercer was also forced to quit the game sooner than he had intended (albeit at the age of 39) when he cracked his leg against fellow Gunner Joe Wade in a league game against Liverpool in 1954. Mark Wright, meanwhile, was ruled out of the 1986 World Cup when he broke his leg in an accidental crunch with Southampton and England colleague Peter Shilton.

Know of any more similar cases? Then fire off an email to knowledge@theguardian.com asap.

PUTTING OFFSHORE ISLANDS ON THE MAP

"A number of Channel Islanders have played in the top English division over the years (Matthew Le Tissier, Chris Jones, Graeme Le Saux)," writes David Glass, "but have there been any well-known players from the other offshore islands - the Isle of Man, the Hebrides, Isle of Wight, Orkney, Shetland, etc?"

It depends on how you define well-known, David. In the late 1980s Cowes High School on the Isle of Wight turned out more footballing talent than an Argentinian barrio. Former Birmingham defender Gary Rowett (who grew up on the island, but wasn't born there) played alongside Southend forward Lee Bradbury in a school side that reached the FA Schools Cup final. Bournemouth striker James Hayter, the scorer of a 140-second hat-trick in 2004, also hails from the island. His mum and dad missed his hat-trick because they'd left to get the night ferry home. "We didn't think James was going to get on," said his father Ben. "We heard a cheer just as we were getting in the car, turned on the radio and found out James had come on and scored."

Rather more tenuously, Wilson Mills points out that League Cup winner Jamie Lawrence spent some time on the Isle of Wight, albeit it at Her Majesty's Pleasure, and was spotted by Cowes Sport scouts while playing for his prison side.

Elsewhere, Norm Calder nominates Johnny MacKenzie from Tiree in the Inner Hebrides. After Scotland played Hungary in 1955, the late, great Ferenc Puskas said he had "never seen wing play of such a high standard", when asked to describe the Firhill Flyer's performance. "This may have been the genesis of Partick Thistle being nicknamed the Maryhill Magyars," says Norm. Travelling further north, Moray Leask and Karl Williamson from Shetland have turned out for Brechin in recent years. In fact, as Neil Ritch points out, Shetland has a history of footballing pedigree - they fought off challenges from the likes of Greenland and the Falklands to win the Inter-Island Games in 2005.

Any more for any more? Then let us know.

THAT'S OUR MORI

Last week we discovered that the aforementioned Australian Damian Mori was the footballer who made the longest commute to training with their club. But, it seems he's been keen to extend his record ...

"He has just been signed by the Queensland Roar from the Central Coast Mariners, meaning he will now travel approx 2,045km from his Adelaide home," writes Sebastian Hare, one of many eagle-eyed readers to update us. Or, as Paul Collier helpfully adds, "4½ hours' flight, 67 hours by car or 80 hours by rail from here in sunny Adelaide."

KNOWLEDGE ARCHIVE

"I remember an Ipswich game that had eight minutes added onto the second half because Alun Armstrong was stretchered off. That surely can't be the longest period of injury-time in history, can it?" asked Alan Cooper back when Johnny Vaughan was seen as the future of television.

Entirely unexpectedly, several of you wrote in citing Manchester United's championship-inspiring injury-time comeback against Sheffield Wednesday in 1993. "It was something like 5.05pm when Steve Bruce scored his second," recalled Richard Fidler. "It was a wonder they got it edited in time for Match of the Day." In fact, there were only seven minutes of injury-time, Bruce smashing his crooked beak against the ball for the equaliser in the final minute of regulation time and then again for the winner in the sixth minute of time added on.

But it was Will Halsey who told us the tale of the mother of all injury-times. "When Brentford played away at Bristol City in 2000-01, there were about 23 minutes of stoppage time in the first-half alone after a broken leg, a dislocated shoulder (Bees striker Lloyd Owusu passed out from the pain and an ambulance had to be driven up to the pitch), and serious concussion caused the delay," noted Will. "In fact, two goals were scored in that first-half injury-time, with the second being clocked in the 67th minute, I believe. The fourth official had originally held up 13 minutes' stoppage time, but one of the injuries occurred in that period to bump it up to 23. I'd be surprised if there were many games that contained more added-on time!"

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"With Coventry having to travel to their game at QPR by Tube last weekend, what other unusual transportation have teams taken to games?" wonders Wing Lau.

"What is the biggest ever upset in terms of Fifa rankings?" asks Yannis Andreas.

"Has a physio ever been sent off? And if both physios were dismissed (for fighting, say), could the match be abandoned?" wonders Dave Griffiths.

"On the back of Nottingham Forest looking to pay £500k to lure Dean Windass to the City Ground, what is the highest transfer fee commanded for a 35-year-old-plus player?" asks Will Hardy.

"Has a referee ever had the bad luck to swallow his whistle during a game?" enquires Christian Gollnick. "And if so, did he survive?"

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