Both players have been brought in for Scotland's second test against South Africa in Post Elizabeth on Saturday.
It was a welcome birthday present for Al Kellock as it's the first time he has been preferred to former Edinburgh colleague Scott Murray.
"It's been a great season and to finish it by getting this start is terrific," he said in The Herald. "It's a very nice way to mark my birthday.
"This is the first time Scott and I have been head-to-head having played a lot together for Edinburgh and Scotland a few times, but there are four or five guys battling for these two places.
"I played against the Barbarians, then was on the bench for the first Test and Frank was telling me I was in the mix and pushing hard. It is only when you get picked to start when these guys are available that you know you've really closed the gap, though."
JP has had little involvement with Scotland's starting XV since captaining his country in Frank Hadden's first Test in Bucharest 12 months ago.
"I hadn't expected this at all, so was quite shocked when the team was read out on the bus. It's been an up-and-down season for me so I'm really excited about this chance to get a bit of closure on it and finish it on a high note," he said.
"When I look at where I was this time last year as captain of my country, then being injured and getting back into the 22 for the Six Nations but not getting a huge amount of game time it is important to get back into the starting side and having a chance to put everything I've got into it."