There were high hopes the Waratahs, featuring the likes of Max Jorgensen, Joseph-Aukuso Suaalii, Andrew Kellaway, Jake Gordon and Pete Samu, could make a major impact this year.
But after starting off the campaign with back-to-back wins, the Waratahs only managed three more victories from their next 12 games, resulting in a lowly eighth-placed finish in the 11-team competition.
The Waratahs' 2026 campaign came to a limp end on Saturday night when they coughed up a 20-7 lead on the way to a 31-25 loss to the Western Force in Perth.
McKellar is contracted until 2027, and is confident he will be given the chance to lead the Waratahs for a third straight season.
"Yeah mate. I'm contracted for next year, and I certainly don't worry about that sort of stuff," McKellar said.
The Waratahs finished with a 6-8 record last year under McKellar before limping to only five wins this season.
McKellar hopes the group will use the pain of their various missed opportunities this year to drive them to greater heights in 2027.
"You've just got to roll with the punches," McKellar said.
"Times like this make the good times feel even better, and they'll come.
"We've got a group here that are buying into what we want to do. Nothing changes from my endÂ
"I'm in this for the long haul, and we'll enjoy a beer together and reflect on the season, and then I'll quickly get to work around turning things around for '27."
Waratahs and Wallabies scrumhalf Gordon could miss the international season after suffering a suspected Achilles tendon rupture against the Force.
Gordon will be sent for scans, but the Waratahs aren't expecting good news.
"He's a tough little bugger, a very resilient sort of character," McKellar said.
"Over the next period of time he'll have his moments no doubt, so we'll make sure we look after him and get around him."
Samu suffered a suspected medial ligament injury against the Force and scans will determine whether he'll be fit in time to take part in the Wallabies' Nations Championship, which kicks off on July 4.
