The 35-year-old made his 318th appearance for the Pilgrims after coming on as a substitute in the 85th minute for a final farewell.
"He was saying to me all second half, 'Don't do it, let's try to win the game and put on another striker'. But someone being at a football club for 11 years doesn't happen a lot these days," Fletcher told the Western Morning News.
"You've got to see the bigger picture, and I think it was important for Romain to be out there one last time in front of the home fans.
"He has been a great servant to the club through highs and lows. I'm sure it has been an emotional day for him."
Larrieu is set to remain with the Green Army after joining Fletcher's coaching staff earlier this season.
