Ames, a former winner of the Players Championship and three other tournaments in his PGA Tour career along with one on the Champions Tour has one hole to play of round two after fog had delayed the start of play and eventually darkness forced a halt with fifteen players still to complete their rounds.
The defending champion Langer is just one behind the leading pair and tied with former USPGA Champion Jeff Sluman and Kirk Triplett.
Jimenez began slowly with bogeys at his 1st and 4th holes but he would play the next 14 holes in 7 under par to take the lead about an hour before play was called. Jimenez played with Langer and Watson so those watching were treated to an absolute feast of high quality golf by all three.
Watson, who won five Open Championships but none at St Andrews, is just two from the lead, is now 68 years old making his effort thus far even more meritorious. Interestingly he tied with Langer for second behind Seve Ballesteros in 1984 at the great course.
Perhaps the highlight of the day for Watson was, interestingly enough, his bogey at the 6th when after playing a provisional from the tee he drove it on the green some 379 yards away. At 68 years of age that was some achievement despite the amount of run on the fairways.
"I have been playing well and I attribute it to practicing quite hard before I came here," said Watson. "I shot 68 on the Old Course under pretty good conditions and I'm very pleased. Anytime I can shoot my age I'm very pleased."
Ames, too, began poorly with two early bogeys but recovered nicely and might yet take the outright lead before all 36 holes are completed.
Peter Fowler is the leading Australian at the halfway mark, the Auckland based 59-year old at 3 under and six shots from the lead.
David McKenzie is another shot back at 2 under, Peter Lonard at 1 under is comfortably inside the cut line and Paul Archbold was unable to repeat his impressive start, a round of 75 today seeing him on the cutline but he has done well all the same.
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