Branden Grace drew on playing an Old Course practice round with former British Open winner Louis Oosthuizen to extend his lead to five shots in the Alfred Dunhill Links Championship on Friday.
The 24-year-old South African, also with Oosthuizen's 2010 Open-winning caddy, Zach Rasego, now on his bag, carded a second round 67 at St. Andrews to move to 17-under par for the tournament.
Grace had teamed with Oosthuizen on Wednesday and carried the information he gleaned into his second round on the famed Old Course in a display that included six birdies, including four in succession from the seventh hole, and only one bogey.
"Playing a practice round with Louis on Wednesday this week on the Old Course definitely helped today," said Grace.
"Louis gave me some lines off the tee which was very helpful, especially with the wind off the left.
"The first six holes are not the easiest driving holes out there, and also having Zach on the bag is a really big help."
Grace arrived in Scotland having won three events this year on the European Tour while he was successful in capturing last week's Vodacom Origins of Golf Final at Fancourt on the South African Sunshine Tour.
It was also at Fancourt in January that Grace defeated US Open-winning compatriots Ernie Els and Retief Goosen in a play-off for the Volvo Champions title.
And Grace intends to continue to draw on that victory heading into the final two rounds of the $5 million Dunhill.
Sweden's Joel Sjoholm matched Grace's round of 67 on the Old Course to move into 12-under par as the Gothenburg-based golfer looks to win for a first time on the European Tour.
The 27-year-old has had three top-10s this year including an eighth place in May's BMW International Open after heading into the final day just one shot off the lead.
Denmark's Thorbjorn Olesen is joint-second after matching Sjoholm's two-round total of 132.
Germany's Martin Kaymer is the best-placed of the four Ryder Cup players competing this week after adding a round of 71 at Kingsbarns to move to three under par.
"I'm very tired, and especially when you don't make the putts," he said.
"It has been a little difficult to get motivated and I had that fantastic experience on Sunday, and I'm still very inspired.
"I'm very motivated on one hand, but on the other, your body is just a little tired, and you have to listen to your body.
"And with all the time changes and the party on Sunday night there, it is what it is. But it's just difficult to motivate yourself sometimes."
After European captain Jose Maria Olazabal received a congratulatory Ryder Cup communication from the King of Spain, Kaymer said he did not expect a similar message from German Chancellor, Angela Merkel.
"Of course, a few athletes were tweeting and e-mailing me, texting me but no, nothing from the German Chancellor," he said.
"I'm sure she heard about it but she has better things to do."