The Arsenal academy graduate has had a hugely successful career in the Championship, helping West Ham, Aston Villa and Luton all achieve the lucrative goal of promotion to the top flight.
But after a debilitating injury in late 2022 left him requiring serious surgery, retirement is now on the cards for the 32-year-old.
Thankfully, though, he already has a new passion on the go, and while it's football related, it's likely a first for players coming to the end of their career.
Explaining his new venture, Grass Gains, to talkSPORT, Lansbury said: "It came about during the first lockdown when I was stuck at home and got into gardening.
"I started to spray my weeds with toxic stuff and put toxic fertiliser down and my missus wasn't too happy about the kids running on the grass straight after.
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"I was trying to usher them off and she said 'why can't they just make an organic fertiliser?'
"I put my head together with my mate and me and the boys have cracked on and taken it to another level."
The product has since crossed the pond into Europe, and Lansbury will soon be heading to Champions League level destinations he once dreamed of as a player.
"We've done Fulham, we've done Genk and we're in at Monaco soon," he said.
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"We're going in the right direction, a few local clubs have asked for it and we've put it down on their pitches as well.
"I want to give back to the local clubs really, I want them to have a nice pitch to play on, there's nothing better than a kid running on a pitch with stripes on it and that's what it does, it helps stripe it off."
Before his injury last year, Lansbury went viral for a lawn-mowing celebration after scoring a stunning long-range strike against Hull City.
He later bizarrely attributed his goal and form to fertiliser, and now all has become clear, with grass treatment his new passion.
Lansbury graduated from Arsenal's academy in 2007 under Arsene Wenger, and he went on to make eight appearances, scoring one goal for the Gunners.
Wenger said Lansbury would 'be a big player for me' after breaking into the first team, but his future ended up elsewhere.
However, one friendship from that era has since been reunited, with Arsenal's groundman put in touch and the product was soon born.
Lansbury explained: "It's taken off really, and during the summer I've not kept fit and I've gone full-time on this, next week we have a meeting with Homebase.
"It was a massive weight off my shoulders really, I was injured before the World Cup and I haven't been the same since.
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"I haven't really got any feeling in my legs, they had to operate and cut all the nerves in my thigh, I can train but it's not been the same.
"Do I go back and try and force it or do I end on a high? My wife wants me out of the house but I said I'll go and cut the grass."