Jordan Spieth has credited hard work for the reason behind his surge back to the world number one ranking.
The 22-year-old American ousted Jason Day from the top spot after winning the Tour Championship by four shots at East Lake on Sunday.
In the final round in Atlanta, Spieth, who has won five tournaments this season, carded nine-under 69, while Day finished tied for 10th place.
"I got frustrated," Spieth said after the tournament. "I missed two cuts in a row, had never done that, lost the number one ranking. I was watching Jason Day just dominate golf.
"I got to work, put my head down a little more than I did right after the PGA, knowing that we could still peak this week and that's what we did."
Spieth, who claimed the Masters and US Open titles this year, also scooped £7.5m in prize money for winning the Championship.
