South Africa's Louis Oosthuizen remained on course to win his first Major title in The 139th Open Championship at St Andrews.
Oosthuizen took a four shot lead over England's Paul Casey into the final round, and was still four ahead as the final pair reached the turn on The Old Course.
The 27 year old opened with seven straight pars and after dropping a shot on the eighth, responded brilliantly with an eagle two on the ninth.
Oosthuizen drove the green on the 352 yard par four and confidently holed from 40 feet to move to 16 under par, Casey then having to hole from eight feet for birdie to keep in touch at 12 under.
Casey had twice covered the front nine in 31 this week but was unable to find such scintillating form when he needed it most, the World Number Ten matching Oosthuizen's 35.
After missing from five feet for birdie on the first, Casey bogeyed the second after coming up well short of the green with his approach, but birdied the sixth from close range and also drove the green on the ninth.It looked like remaining a two-horse race between the leading duo, with Martin Kaymer, Lee Westwood and Henrik Stenson four shots further back.
None of the contenders had been able to mount an early charge, with five of the six players in the last three groups going to the turn in 35.
England's Luke Donald finished birdie-eagle to join Spain's Alvaro Quiros and American Jeff Overton as clubhouse leaders on five under.
Casey's fading hopes were dealt another blow with a triple bogey on the 12th after he drove into the same gorse bushes found by Kaymer in the group ahead.
Kaymer escaped with a bogey five, but Casey's third shot came up short of the green, his fourth ran through the back and three putts all added up to a not-so-magnificent seven.
Oosthuizen showed no mercy, rolling in a birdie from 12 feet to improve to 17 under par and an eight shot lead, with Westwood joining Casey on nine under with birdies on the 13th and 14th.
