Number two seeds Heliovaara & Patten began the match the stronger, forcing two break points in both games two and six, but the Austrian and American duo managed to defend.
The Finn and Brit were at risk of losing serve in game nine, but survived the only break point they conceded in the first set, before earning another two break points to win the set off Erler's serve in the next game, but again they couldn't take advantage.
The consistency they had shown in the set served them well in the tiebreak, as Erler & Galloway lost their first two serves as the champions went 5-0 up, before eventually taking the tiebreak, 7-5, and the first set, 7-6.
But their opponents really stepped up at the start of set two, losing only two points across their first three service games, and crucially took the fourth game off the serving of Heliovaara.
Erler & Galloway, ranked 43rd and 39th in the world, never came close to losing serve throughout the second set, and levelled the match up at one set all, with a 6-3 victory. En route to winning the doubles title in Melbourne a year ago, Heliovaara & Patten didn't lose a set until the Semi-final stage.
Things could have got worse for the title holders when the Austrian and American had two break points in the first game of the third set, but Patten held serve, before he and Heliovaara went on the attack, setting themselves up for three break points off Galloway's serve, and finally forced a loss of serve with the third of those.
The pair tied third in the world rankings survived one final scare in game seven, holding serve despite two break points, before winning the match in a mammoth game nine, which they took on their sixth match point.
The 7-6, 3-6, 6-3 win for Heliovaara & Patten sets up a Third Round meeting with Czech duo Petr Nouza and Patrik Rikl.
Follow the 2026 Australian Open men's doubles on Flashscore.