So, you think you’ve had a bad Monday returning to work after a summer holiday? Stop there, and put yourself in the shoes of Australian golfer Cameron Davis for a minute.

Yes, Davis is already rich and yes, his week in idyllic Maui was still a lucrative one, but one basic error in the final round of the US PGA Tour’s year-opening The Sentry tournament has cost him $490,000.

The mistake was one he shared with American playing partner Will Zalatoris, and it was as basic an error as a golfer can make – they both hit each other’s ball.

Each player is responsible for identifying and hitting their own ball with each shot. When they don’t, the blame falls on them alone.

The penalty for such a mistake is punitive and immediate – a two-shot penalty to both players and a re-hit of that particular shot. On Monday (AEDT), this resulted in Davis bogeying the par-5 15th hole.

Two shots over a 72-hole tournament don’t sound like a lot but when it happens late on the final day the importance is magnified.

Davis finished the tournament in a tie for 13th. A transfer of US$410,000 ($A658,00) will lob into his bank account soon enough. But, if you take that two-shot penalty away, Davis would have finished in a tie for fifth and pocketed US$715,000 (A$1.15 million).

Both Davis and Zalatoris were understandably aggrieved after realising the errors that had been made. It’s probably for the best that the cameras were focused on other players at the time.

Davis’ career earnings will now be approaching $25 million, but that would be of little solace right now.

The tournament in Maui, held at the Kapalua Plantation course, carried US$20million in prize money. Japanese star and former US Masters winner Hideki Matsuyama won to claim the US$3.6 million.