Chelsea youngsters Callum Hudson-Odoi and Reece James handed manager Frank Lampard a double fitness boost after coming through unscathed on their return from injury.
Hudson-Odoi, 18, had been sidelined since April after rupturing his Achilles in the Europa League semi-final against Eintracht Frankfurt and was expected to be out for around six months.
But the Blues winger returned to full training ahead of schedule in August and was made available for the development squad to build his match fitness.
The England international looked sharp on his first appearance, playing for an hour before being replaced by Faustino Anjorin.
It was also a successful night for 19-year-old full-back James, who was making his first appearance since suffering a serious ankle injury at the Under-20 World Cup with England in the summer.
The full-back shone during a loan spell with Championship outfit Wigan Athletic last season and was drafted into the senior squad as back-up for Cesar Azpilicueta, but was denied a full pre-season following his injury.
However, James managed to get through 45 minutes before being replaced by Thierno Ballo suggesting he too could be ready for first-team action.
Both players were involved in the build-up for Chelsea's first goal as Hudson-Odoi set up Henry Lawrence for the opener.
Marcel Lewis doubled the advantage midway through the second half before Brighton scored late on through Alex Cochrane.
