The England international captained Leicester Tigers Development XV to a 48-19 win over Gloucester United in the Guinness A League at Welford Road.
Deacon played the first-half on his return from a back injury that has kept him out since the EDF Energy Cup Final at Twickenham in April.
He said: “It’s been a long time since I played – too long really. It’s been about eight or nine months and it is nice to be back.
“There were no problems with my back at all so, hopefully, I can kick on from now and play a bit more next week.”
Flanker Ben Woods returned from a knee injury to score a hat-trick, Alesana Tuilagi, who was also coming back from a knee problem, grabbed a try and there were also scores for Sam Vesty, Dan Hemingway, Ben Pienaar and Tom Varndell.
Deacon said: “It was a really good team performance. As well as me, there were a few others who have been out injured and a lot of the other guys haven’t played a lot recently.
“They had a point to prove and the way the guys played showed that.
“We said before the game that we wanted to run it a little bit and run around and I think the guys enjoyed it.”