However, a Rhys Webb-inspired Ospreys got the better of them in the reverse fixture, securing a 31-20 triumph at the Liberty Stadium the following month.
Both sides went on to finish in the top four of the GUINNESS PRO12 table, only to suffer defeat in their respective play-off semi-finals.
They kick off the new season against one another in Belfast on Friday night and Doak is expecting a tough test from the first whistle.
"The Ospreys are a good side," he said. "We've got to sit down during the week and take a look at a couple of things from our meetings last year.
"We know each other pretty well. We know their strengths, it's going to be a physical game, we've just got to make sure we get in the right areas and take our opportunities.
"It's a key aspect of the game that has been a bugbear of mine for a few seasons - being clinical. We've got to make sure we turn it around for next week."
Ulster have not enjoyed the ideal preparation for the season, with pre-season defeats at the hands of Leinster and Edinburgh, but Doak believes they are not far off their best.
"We're getting in the right areas, it's just about completing the score," he added.
"Last week we missed a couple of chances too and if we take those chances we're 20 points up at half-time and it's a different game and a different mindset going into half-time.
"We've got to learn from that very quickly because we've got a big opening game in the PRO12."
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