It capped off a decent day on the course for Hillier, who finished his round four-under-par to sit in a tie for fourth with three other players.
Along with his ace, Hillier carded five birdies to cancel out three bogeys – two of those coming in his front nine.
Three birdies in a row on holes 12, 13 and 14 saw him put his round on the right path, with his last dropped shot of the day coming on the par-four 10th.
Hillier ended the day one shot off the lead, held a five-under by Scottish duo Grant Forrest and Connor Syme, and Spaniard Eugenio Chacarra.
“It’s pretty tricky out there. A bit of wind blowing now. The greens are obviously very soft, so it’s kind of hard to control the spin. I think I managed it well today and hopefully I can keep doing that for the rest of the week,” he told Ten-Golf.
The tournament shapes up as the start of a big run for Hillier, who is looking to claim one of the 10 available PGA Tour cards on offer in DP World Tour, often referred to as the European Tour, this year.
As part of a pathways partnership with the PGA Tour, the top 10 players at the end of the DP World Tour not already exempt earn entry onto the American tour for 2027.
Heading into this weekend’s tournament in Spain, Hillier sat 13th on the DP World Tour leaderboard, holding one of those 10 tickets to the PGA Tour.
Including this weekend’s event in Spain, there are five tournaments left on the DP World Tour schedule this season, with one in India next week and a South Korean tournament the following week before the season concludes with limited-field events in Abu Dhabi and Dubai.
Fellow Kiwi Kazuma Kobori had a rough start to his week in Spain, finishing his first round at six-over to sit well down the leaderboard.
Christopher Reive joined the Herald sports team in 2017, bringing the same versatility to his coverage as he does to his sports viewing habits.