The pair have swapped ownership of the lead of the 2019 championship multiple times already this season after just five races and five Mercedes one-two finishes.
With Hamilton's victory at the Spanish Grand Prix, it is the five-time champion who will head to Monaco with the championship lead however Bottas is focused on beating Hamilton all the same.
"For now, between me and Lewis, but it's a massively long season. There are many teams that, especially at some tracks are very close and it's going to be a big development race between teams all through the season.
"But if it's going to be me and Lewis, every single opportunity will be key.
"That's why (Barcelona) for me was annoying. I felt I worked hard for this weekend and for the qualifying, to be on pole, on this circuit where it means a lot and I lost it at the start."
The Finn has already enjoyed a much better start to the current season versus 2018, winning two of the five races so far this season.
With Ferrari also looking a distant threat now after the Italian team's woeful start, Bottas knows it could be his best chance of a title challenge.