The shock defeats of Manchester City by Bodo/Glimt in the Champions League and of Crystal Palace by Macclesfield in the FA Cup last month had one thing in common - both ties were played on plastic pitches.
Four English clubs - QPR, Luton, Preston and Oldham - had such surfaces in the 1980s and early 1990s, before they were banned from the English professional game over issues with ball roll and bounce and fears over long-term injuries.
They have not been allowed since in the Premier League or Football League, with any promoted clubs who play on artificial surfaces - such as Sutton United in 2021 - having to replace them with grass pitches.
The City and Palace results should serve as a warning to Brentford, who are the next side to visit Macclesfield in the FA Cup, in the fourth round on Monday.
While neither Pep Guardiola or Oliver Glasner blamed the pitches for their defeats, Bees boss Keith Andrews will need to have his preparation spot-on to avoid becoming the victim of another giant-killing.
And given our performance in the FA Cup third round at Sheffield Wednesday, I think he will.
Although we played Arsenal on Thursday night and the Moss Rose tie is on Monday, I am sure that Andrews will find time to train the squad on an artificial surface ahead of the game, if he hasn't done so already.
I also think that - as at Hillsborough - he will name a strong matchday squad to avoid any slip-ups.
You could argue that artificial pitches should be banned from all competitions as they give the clubs who play on them every week an unfair advantage.
However, I don't think that would be right.
All grounds have their own quirks with which the home team are familiar, so sides just have to get on with it and not make excuses - not that Brentford would if we got knocked out.
Find more from Ian Westbrook at Beesotted podcast