Mickelson turned in the best fourth-round score with a 65 that was 10 strokes better than the third-round 75 he produced between Saturday and Sunday.
Spieth, who played alongside Mickelson, produced a 66 to climb into a tie for fourth. He also improved his score by 10 strokes after a third-round 76 wrecked his chance of catching the leaders.
Reed's 68 placed him inside the top 10. He had four steady rounds and he was the benefactor of some less-than-ideal rounds from other contenders to land in a tie for fourth.
Each of those three golfers were previous champions at Augusta, and they knew exactly how to approach the course in its Sunday setup. The flag locations are typically the same for the final round.
None of the past champions had a chance of chasing down Rahm, but they were able to turn in the best possible finishes to earn more prize money and create some momentum going into the season's three other majors. Next up is the PGA Championship at Oak Hill Country Club in Rochester, New York, from May 18-21.
