"Which players have gone under the cosmetic surgeon's knife to enhance their looks?" wonders Philip Genochio.

Rumours spread among the Brazilian press in 2009 that Ronaldo had undergone liposuction. Joaquim Grava, the doctor at Corinthians, where Ronaldo was then playing, said: "There are certain things a doctor can talk about, but others only with the consent of the patient. I am not allowed to confirm if the [surgery] has been done or not." Most cryptically, when asked directly whether he'd had the procedure, Ronaldo replied: "I don't know, I don't even know if I did it. These are things we don't know ... What I do with my private life is my business."

There is no doubt about the former Colombia goalkeeper René Higuita, however, who underwent surgery for all to see on the television reality show, Cambio Extremo, in 2005. "I am tired of being ugly René, I want to be handsome René," he declared. As reported in the Observer, "Higuita had televised nose surgery, a silicon chin implant, skin peel, eyelid skin cut away, 'aggressive' liposuction and abdominal muscle enhancement after being voted Colombia's 'ugliest icon'. After a month in isolation Higuita revealed his brand new look. 'Bodily, I am perfect,' he said."

Next up is Sasa Curcic, once of Bolton, Aston Villa and Crystal Palace, whose wife Lisa told the Sunday Mirror in 1998 of the Serb's nasal surgery. "Some of [my friends] couldn't understand why I'd fallen for someone with such a big hooter," she said. "But I've never been attracted to pretty boys and I thought he had an interesting face and lovely eyes." She went on to explain that Curcic was operated on at a private London hospital, having complained about problems with his breathing. "Well, that was his story," said Lisa. "I think it was more to do with vanity because he was always telling me he'd like to have a nose like mine. He got into trouble with Villa because he didn't tell them he was having the surgery and it meant he couldn't play until it had healed." Villa's secretary-director Steve Stride confirmed this to the News of the World in 2000, saying: "While [Curcic] was with us he had his hair dyed, his teeth capped and underwent plastic surgery on his nose. I think he was trying to make himself more attractive to women but I suspect it had the opposite effect." Here's a more recent picture.

Obviously there are a host of players that have had operations caused by injuries on the field of play. Then Liverpool striker Peter Crouch is just one example, telling the Daily Post in 2007 of his need to correct a broken nose sustained in a collision with Rob Hulse. "If it's affecting my performances I'm going to have to get it done," he said. There are also off-field injuries which have required some work. Earlier in 2010, Diego Maradona was bitten by his pet dog in Buenos Aires and headed off to the local Los Arcos clinic for surgery. "He had a simple lesions and had surgery for about half an hour," said Julio Jiminez, the clinic's administrator. "There's no problem. He was walking and left with his girlfriend."

Finally (and admittedly rather tenuously), plastic surgery can come back to haunt footballers, as it did with Lothar Matthäus. His estranged wife, Liliana, demanded that the former Germany skipper foot the €2,800 bill for a breast augmentation reversal. "I fail to see why I should pay for this and other plastic surgery bills," Matthäus told Bild.

Any more for any more? Send them to the usual address.

TIGHT AT THE TOP

"With the recent end of season shenanigans in F1 where four contenders could statistically win the title in the last game of the season," begins Paul Baker, "I was wondering which league had the most amount of teams fighting for the championship on the final day? And conversely, which league has had the most amount of teams fighting relegation on the last day?"

Richard Ailes mails in with news from Mexico. Please try and keep up. "On Thursday, 19 April 2001, the final day of the Mexican season, the title aspirations of 16 of the 18 teams in the First Division remained intact," he begins. "True, we're taking about a 'regular season', with 'post-season' play-offs (called 'Liguilla' or 'mini-league', though it is run on a knock-out basis) to follow, but it's nevertheless worth documenting what was the high noon of a system of competition so complex and inclusive that television coverage of the last day of the season resembled an Election Night Special, with a baffling array of possible outcomes rotating with almost every goal.

"In order to work out who was going to be in the play-offs you had to cross-reference two different league tables: a regular, common-or-garden league table, and a 'groups' table, which repeated the information on the league table but arranged the teams in four random groups. To qualify directly, a team needed to finish in the top eight of the regular league table and in the top two of its random group; teams which only met one of these criteria would have to play against a team meeting the other requirement in a pre-Liguilla 'reclassification' duel. Thus, theoretically, 11 teams could get to the post-season. And the hopes and dreams of the mediocre were further bolstered by the short, twice-yearly seasons, which gave little time for a gap to open up. At the Estadio Jalisco that evening, for example, I watched 12th-placed Atlas scrape into a reclassification with just 22 points from a possible 51 (not that we had much of a clue, mind you, without Peter Snow to guide us ...).

"Meanwhile, over in Mexico City, 23 points was enough to earn Atlante (eighth in the overall standings, top of their random group) a direct place in the Liguilla. Or it would have been, had it not been for a third league table. Relegation was decided on a three-year points-per-game average, and Atlante's final-day defeat to local rivals América meant they were down. The first team to be relegated and make the play-offs simultaneously, Tigres UANL, had actually competed for the championship as a relegated team (passing reclassification and going out in the quarter-finals), but a subsequent ad hoc ruling prevented a repeat occurence, and Atlante were forced to relinquish their play-off berth along with their top-flight status. León, the team that leap-frogged them on the last day, not only survived relegation but qualified for the Liguilla as well."

There's more. There's always more, as Darren Beach explains of goings-on in Japan. "The 2005 J-League was the first since 1996 to be run on a European-style single season rather than the South American-style double-season format followed by a play-off to decide the champion," he writes. "With one match left in the 34-game season, five clubs had a chance of the title – leaders Cerezo Osaka on 58 points, then neighbours Gamba Osaka on 57, and then Urawa Reds, JEF United and Kashima Antlers on 56 points.

"On the final day, Gamba, Urawa and Kashima all won their final matches comfortably. JEF beat Nagoya 2-1 after being 1-0 down after 88 minutes (Leicester's Yuki Abe scored the winner), while Cerezo were leading FC Tokyo 2-1 with two minutes left, with one hand on the trophy, before a late equaliser handed the J-League title to their neighbours Gamba. Final standings: 1) Gamba 60. 2) Urawa 59. 3) Kashima 59. 4) JEF 59. 5) Cerezo 58."

STADIUM PIPE DREAMS (3)

In the last two weeks we have looked at ambitious stadium plans that failed to get off the ground. But here's a belter that slipped through the cracks ...

"Your feature on unlikely stadiums mentioned Luton Town, and this reminded me of a scheme their chairman once had that gave all us rival fans down the [Vicarage] Road a good laugh," begins Gavin Cleaver. Have a look at this, and especially section VII on 'Development'. The second best bit is:

'A new stadium built on a concrete raft over the current M1 spur road adjacent to our site between junction 10 and 10a. The stadium would have a 'Teflon' roof kept up by air pressure similar to the Pontiac Dome in Detroit, Michigan. The stadium would have capacity for 50,000–75,000 people with a concentration on executive boxes and executive areas.'

"Yes, a stadium on a platform high up in the air. This isn't even the best part. What would be the reason for putting the stadium up in the air? Why, that would be the possibility of ...

... 'an alternative scheme drawn up where the roads on the site would provide the possibility for a motor racing track. Planning permission will, therefore, be sought for a F1 track on the site. The Borough has indicated they would support this application. If the application were to be successful there would be one Grand Prix a year held on the site, which would attract income of more than £500,000,000 with a profit to the club of some £200,000,000. This one event would make LTFC the largest (in financial terms) club in Europe.'

"Yes. A floating stadium with the Formula 1 Luton Grand Prix underneath. Best. Plan. Ever. (This came shortly before Luton fans were encouraged to phone a premium rate phone line to vote for their new manager). Their club continues to provide us with chuckles galore even in these dark, dark times."

KNOWLEDGE ARCHIVE

"My late uncle was a footballer playing for pre-communist China. He always boasted that he participated in the 1948 London Olympics. Was there a Chinese football team? And if so, have you got any details of the team and how did they do?" wrote Rebecca Yau in 2008.

Good news, Rebecca, your uncle was not a fibber. The Republic of China did indeed send a football team to the London Olympics in 1948, though sad to relate, their success was limited. They lined up for their first round match against Turkey at midday on August 2, 60 years ago, at the home of football, Green Pond Road, Walthamstow. They finished up on the wrong end of a 4-0 walloping, but were saved from any embarrassment by the USA's 9-0 capitulation to Italy hours later. And wearing the No5 shirt in that defeat was Man Chi Chau, Rebecca's late uncle. The team line-ups, goalscorers and all the other results can be found in Fifa's excellent archive.

It would only be fair to note the football team's achievement in simply lining up at the Olympics. The Chinese government gave next to no funding to its Olympic delegation. In order to secure the finances to fund their Olympic journey, the football team embarked on a 32-match tour of Asia, pocketing their share of gate receipts as they went. The delegation even brought with them their own food, to save on inflated prices in post-war Britain.

The Chinese Olympic team that year featured 33 athletes, all of them male, none of whom made it beyond the preliminary stages of their event. The delegation was then forced to borrow money to make it home. It would be fair to say that state funding for Chinese athletes has seen something of an increase in the last 60 years.

For many more sepia-tinged questions and answers, visit the Knowledge archive.

CAN YOU HELP?

"The last time Rangers lost a game which they were winning at half-time was in November 1998, away to Parma in the Uefa Cup," says Mark MacDonald. "That is now over 600 games ago. Any idea what the longest run of games is for a club not losing a game which they were winning at half-time?"

"Which is the world's most popular team among current and former heads of states?" asks Alon Ravid.

"After watching Stockport record their third 5-0 shellacking in a month, my friends and I were wondering what the record for most 5-0s in a single season, and the most for a club that wasn't relegated," writes Andrew Pechey.

"Having heard about the Xabi Alonso/Sergio Ramos 'deliberate' red cards in Ajax v Real Madrid, my memories went back to the coverage of FA Cup football in the early 1980s when I was a boy in Holland," begins Hans Baas. "There was a team captain who got a yellow and desperately tried to get a second one to be able to play the final, but the ref categorically refused to give it. Can you please tell me if this happened, and how and when? It might be to do with the 82-83 Brighton run, but I can't find any information to confirm my memories."

Send your questions and answers to knowledge@theguardian.com.