Duplantis cleared 5.80m at the first attempt before vaulting 6.00m on his second try, and that was all it took to win the event in Oregon, as his closest challengers Sam Kendricks and Austin Miller failed at 5.90m.
The win means "Mondo" has now won all five men's pole vault events to have taken place on the Diamond League circuit in 2025.
At the previous meeting in his native Sweden, Duplantis had broken the world record for the 12th time at 6.28m, and claimed afterwards that 6.30m and even 6.40m were in his sights.
However, today in the USA he set the bar just one centimetre higher to 6.29m, yet the attempt at a 13th world record remains unlucky for now, as the 25-year-old failed with his three vaults.
His next chance to sail over 6.29m or even higher could come in next week's Diamond League meeting in Monaco, as Duplantis continues preparations for this summer's World Championships in Tokyo.