Vorab:
Please refer to gross scores, not +-Par. The latter is too ambiguous.
You played 27 and 29, counting to the average as 54 and 58.
Depending how many Legend rounds you have under your belt, the influence on the average may be minimal - "law of the big divisor" - up to 500 for us Legends.
Looks as if your average is saturated(?), or close to it...
Mottikowski: To become a Tour Legend I would have to play another 300 rounds at this pace... from 65 to 59?
Nope.
Our goal is NOT to diminish the average. It's about the remaining pool of scores.
You just have to eliminate enough high scores and add low scores to end up with a mix of 500 scores resulting in the appropriate average ;)