The phoney war, otherwise known as the regular season, is over and it is sudden-death time in Super Rugby.
For the Highlanders, moderately buoyant after winning four of their past six games, that means a challenging trip to Canberra this weekend to play the Brumbies, knowing victory means they are one step away from a shock appearance in the final but defeat means the season is done.
"It’s a pretty special time of the year," Donnelly said.
"Playoff footy is different to normal footy. You start back at zero, and sometimes it’s not the best team that wins but it’s the best team on the day.
"Our focus is on preparing really well so we can go over to Canberra and put in a great performance."
Donnelly admired the fact the team from the Australian capital had added speedy game-breakers and a willingness to use the ball to their impressive set piece and hefty maul.
But the Highlanders had taken some confidence from the clash in Dunedin earlier this season. The Brumbies won 27-21 but had to scrap to get there.
"We certainly started really well in that game but we just made a few too many errors with the ball," Donnelly said.
"We put them under a lot of pressure to start with and then I suppose we allowed them to play their game and they ground us down a bit towards the back end of the game.
"Our focus is on starting well and limiting our errors. You’ve got to play right to the 80th minute. Games are tight and you’ve got to keep executing right to the end."
The Highlanders should effectively have everyone on deck this week, though midfield back Tanielu Tele’a is an uncertain starter with his knee problem.
Lock Will Tucker cleared the next stage of HIA protocols, and rising first five Cameron Millar is available.
Millar, halfback Folau Fakatava, lock Mitch Dunshea, loose forwards Oliver Haig and Sean Withy, and outside backs Timoci Tavatavanawai and Jacob Ratumaitavuki-Kneepkens will probably return to the starting XV.
Fullback selection could be up for debate, though, after youngster Finn Hurley shone in his first start in the 41-14 loss to the Hurricanes in Wellington.
"Conditions for the back three were pretty tough but I thought he excelled," Donnelly said.
If things go wrong in Canberra, it seems likely it will spell the end of his time at the Highlanders for captain Billy Harmon.
The outstanding loose forward has not yet confirmed his future but there is strong speculation he is heading to Japan.
"He leads really well. He leads with his actions on the field. He brings a lot to our team."
