Donnie's good form for Glasgow saw him selected for Scotland's tour to Australia and he grabbed his opportunity with both hands.
"I was a bit under the weather for the first couple of weeks, I am not a very good flyer and always seem to pick something up on these long flights, he says. "But by the time the Samoa match came round, I was feeling fine. It was a brilliant game to be involved in. As physical as you would expect a Samoa match to be. I think we played pretty well. It is just a shame that it was not shown over here.
"The Australia Tests were an amazing experience, a massive step up from my previous caps, if only for the venues. I saw for myself how teams like that will really punish any missed tackles or other errors.
"We were very much in the game, especially in the first Test, but a couple of small mistakes, they pounced and exploited them."
Donnie is regarded as being Scotlsnd's only genuine openside flanker well-versed in the art of scavenging ball.
"He is always sniffing around the ball," says Hugh Campbell, his coach at Glasgow and the man who was in charge of the international forwards when Donnie won his first caps two years ago in North America. "Donnie is a very under-rated player, the only genuine No7 in we have in Scotland."
Donnie acknowledges that he was seen mainly as a destructive, ball poaching flanker but perhaps lacked finesse in the more constructive aspects of the game.
Hugh believes the new approach is working already. "He has come on a lot," he says. "We have worked on the specialist aspects to his game, handling and support lines and all that, and compared to a couple of seasons ago, he is more confident on the ball and offers a lot more options in support and ball in hand."
Both Hugh and Donnie agree that racing back to the heart of Scotland's plans has revived the player's self confidence and whetted his appetite for more. "The Scotland tour has taken him to another level," says Hugh.
As far as Donnie is concerned, getting back into a Scotland shirt has blown away all the frustrations of the past year: "The tour experiences were a massive motivation for me," he says. "Even though we lost both times to Australia, beating Samoa and the whole experience has re-ignited me, a real incentive, I want to be back involved in days like those."
You can read Lewis Stuart's Sunday Times article here