They were close buddies, and had played with and against each other in many tournaments as amateurs.
As professionals - where the play-for-pay credo puts a heavy demand on their careers - their tournament meetings became fewer and fewer.
Next week, at the Asian Tour's inaugural US$750,000 (S$1.05m) The World Classic Championship at Laguna National, they will play together as professionals for the last time.
Lam Zhiqun, 26, who turned pro in 2011 and earned a spot for the Laguna event through the Singapore Professional Golfers' Association's Order of Merit, is returning to his amateur status because of work commitments.
And Choo, 28, who also turned pro five years ago, will be competing as a sponsor's invite for the big event at Laguna's World Classic.
Lam, who is in Bali on business, said: "I haven't been playing golf for a few months now after taking on a new job. So it's better that I switch status."
Choo, who is lying joint-28th after the second day of the PGM Tiara Championship, an Asian Development Tour event in Malacca, is hungry for success after a stellar amateur career.
The promising player is chosen as a sponsor's invite. The other is up-and-coming Jonathan Woo, who turned pro four months ago after an amateur career (like Choo) with a stint at the collegiate events in the United States.
Singapore will have 11 other players in the event, starting next Thursday.
Among them are No. 1 player Mardan Mamat and Lam Chih Bing, who won automatic berths.
Lam is playing at the US$400,000 Panasonic Open in New Delhi while Mardan is taking a week's break suffering from a nagging right shoulder injury.
Mardan, who played in last week's CIMB Classic in Kuala Lumpur with a slight shoulder pain, withdrew from the Indian event last Thursday.
"I'm keen to play in Laguna, a favourite venue of mine. After next week's event I have a busy schedule ahead, so I thought that it was best that I recover fully," said Mardan.
The other nine players slated to play are Quincy Quek, Koh Dengshan, Goh Kun Yang, Marc Kawasoe, M. Murugiah, Poh Eng Wah, Chang Ren Chiat, Vincent Khua and Justin Han.
An eclectic mix of players from over 23 countries will feature on the Laguna layout, touted as Asia's "Tougest Test".
No fewer than 35 Asian Tour winners, including four Order of Merit champions, will headline the Tour's only stop in Singapore.
Among them are reigning Order of Merit champion David Lipsky (United States), Australian Scott Hend, Thai veteran Thaworn Wiratchant and India's SSP Chawrasia.
This article was first published on November 6, 2015.
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