The lucrative head-to-head showdown between Tiger Woods and Phil Mickelson was struggling to live up to the hype as both players failed to find their best form over the front nine at Shadow Creek.

Much had been made of Friday's matchplay contest between Woods and Mickelson, with a $9million prize on offer to the winner and further money going to the players' respective charities courtesy of a range of side bets during the round.

However, neither man was able to shine over the opening nine holes, which ended with Mickelson one up, prompting some good-natured criticism from fellow professionals on social media.

Rickie Fowler suggested mattress company Tempur-Pedic could sponsor the contest, adding: "Bit of a pillow fight going right now haha".

European Ryder Cup captain Thomas Bjorn was more concise, but nevertheless made his feelings clear as he tweeted a sleeping emoji.

As the action involving Woods and Mickelson failed to offer much in the way of entertainment, former NBA star Charles Barkley - working as a television pundit at the event - was handed a challenge of his own by Houston Astros pitcher Justin Verlander.

After Barkley had derided the performance of both players, Verlander tweeted: "Barkley saying it's not good golf. I wanna see Tiger and Phil throw down a challenge bet at him. 100k for double bogey or better on #1. C'mon Charles, I know you got your sticks with you."