“Birmingham took the unusual step of retiring Jude Bellingham’s No 22 shirt after the teenage prodigy secured a move to Borussia Dortmund. What other clubs have retired shirt numbers in honour of players? And, if there are others, are Bellingham’s 44 appearances a record low for the bestowing of this honour?” asks Derek Robertson.

We covered Derek’s first question back in 2009, with Franco Baresi, Paolo Maldini and Bobby Moore among the legends whose shirt numbers were retired. There have been plenty of examples of a shirt number being retired in honour of a younger player – most, sadly, in more sombre circumstances than Jude Bellingham’s.

“QPR retired the No 31 shirt in memory of Ray Jones,” writes Edar Mullan. “The promising young striker had scored six goals in 37 appearances for the Rs before he died in a car crash in 2007, three days short of his 19th birthday.

The list of players whose shirt number was retired posthumously is tragically long. Those who made fewer than Bellingham’s 44 appearances include Marc-Vivien Foé (Manchester City, No 23, 38 appearances), Michael Maidens (Hartlepool, No 25, 31 apps), Mark Philo (Wycombe, No 14, 17 appearances), Cheick Tioté (Beijing Enterprises, No 24, 11 appearances) and Dylan Tombides (West Ham, No 38, one appearance).

Of those whose shirt number was retired while they were still alive, one man stands out: Austrian journeyman and cult figure Stefan Maierhofer. “The tall striker is not the most gifted footballer, but is rather known for his work ethic and his incredible self-esteem,” says Michael Gahler. “In November 2014 he joined SC Wiener Neustadt on a short-term deal until the end of the season. He had the option to terminate the contract if a foreign club came in for him during the January transfer window, and he joined Millwall for a second time after less than two months with Weiner Neustadt.

“He had worn No 39 while at the club (it wasn’t his regular shirt number – I guess he just took some random number that was not occupied since he joined in the middle of the season), and when he left the club decided to retire his shirt number. ‘As a motivator he influenced the team with his positive energy during a difficult spell, they explained, ‘and he helped SC Wiener Neustadt to gain previously unknown public perception.’

“Sadly his time at the club didn’t help them avoid relegation from the Austrian Bundesliga. They haven’t returned to the top flight since.”

The longest unbeaten home runs

“Liverpool have gone three straight league seasons without a home defeat. What’s the record (English, European, worldwide)?” wonders Boris Cule.

As great as Liverpool have been at Anfield in the last few years, their unbeaten run of 59 league games and three full seasons barely registers on the fortressometer. According to the wonderful RSSSF site there are at least 19 clubs who have had longer unbeaten runs at home – including Liverpool themselves, from February 1978 to January 1981. That only took in two full seasons, but the run lasted 63 matches in total.

The best of the Premier League era is Chelsea, who went 86 matches and four full seasons without defeat at Stamford Bridge from March 2004 to October 2008, when they were beaten 1-0 by, yep, Liverpool. But when it comes to fortresses, nothing compares to the Bernabéu in the late 1950s and early 1960s.

Real Madrid were unbeaten in 121 league games – and seven full seasons – at home between February 1957, when they lost 2-0 at home to Atlético Madrid, and March 1965. The run ended in painful circumstances for Madrid when when Jorge Mendonça (no relation) scored the only goal to give Atléti a famous victory.

Most draws in a promotion season

“West Brom drew 17 Championship games last season – is that a record for a promoted side?” asks Karin Sundmark.

That’s an excellent spot, Karin, but it’s not quite a record. Our first thought was Italy in the days when backpasses were still allowed, and Serie B didn’t disappoint. In 1991-92, the last season before the introduction of the backpass law, both Brescia and Ancona were promoted after drawing 21 of their 34 league games. Ancona’s away record was particularly special: 19 games, one win, 15 draws (F-I-F-T-E-E-N), nine of them goalless. And to think some people thought the backpass law was a bad idea.

Pisa did even better in 1981-82, drawing 23 of their 38 games on their way to promotion to Serie A. And spare a thought for Perugia. We all know about the 1978-79 season, when they were unbeaten in Serie A and still didn’t win the league. Six years later they lost only one of their 38 Serie B games in and still finished two points off promotion. If only they had been able to turn a couple of their TWENTY-BLOODY-SIX draws into victories.

Knowledge archive

“Ken Dodd and other comedians of his era were fond of belittling their modern counterparts by saying that if they want to be compared with the old guys, they should try playing the Glasgow Empire on a wet winter Monday after Rangers and Celtic both lost at home on the Saturday,” explained in November 2003 Tom Paternoster. “Given that these two only seem to lose two games a season, has this scenario ever actually happened?”

It’s highly unlikely, Tom. Because not only do Rangers and Celtic rarely lose on the same day, they also aren’t allowed to play at home on the same day – though on 19 April 1972, Ibrox was full for a Cup Winners’ Cup game against Bayern Munich just as Parkhead was for a European Cup game against Inter, which is to say that roughly 18 percent of Glasgow’s population went to the game that night.

But, home or away, the Old Firm are not invincible and sometimes, they have to lose. And we’re still betting that if Ken Dodd had played the Empire on Thursday 23rd August 2001, the day after Rangers and Celtic were beaten in the European Cup by Fenerbahce and Ajax respectively, the gig would have gone down about as well as Peter Ridsdale wandering into a Leeds tavern on a Saturday night.

Can you help?

“Leon Balogun finished his 2019-20 season with Wigan at around 9.30pm on 22 July and started his 2020-21 season with Rangers at 12.30pm on Saturday 1 August. Has there ever been a shorter gap between a player’s domestic seasons?” asks Mike Peter.

“Way back when, it was common for teams to be managed ‘by committee’ rather than an individual manager. Which was the last team in the Football League to switch to the modern system?” asks James Murton.

“I ended up on the Ukrainian Premier League Wikipedia page and noticed that recurring champions Shakhtar Donetsk went top of the table way back in Gameweek 1 on the 31 July 2019 with a 3-1 win away to Oleksandriya and never dropped off the top spot all the way to the end of the season. Has this occurred in many other leagues? (I have an inkling PSG or Bayern may have done it in recent years)” – Dean Whearty.

“Martin Kamburov was recently crowned top scorer in the Bulgarian top-flight for the sixth time. He first achieved this in 2003-04. Has a player ever won two Golden Boots so far apart?” asks Ruairí Cullen

• Send your questions and answers to knowledge@theguardian.com or tweet @TheKnowledge_GU.