Tom Brady could play well into his 40s after the Patriots traded their back-up quarterback Jimmy Garoppolo to San Francisco.
The 49ers have acquired Garoppolo from New England for a second-round pick in the 2018 NFL entry draft, meaning Brady - who turned 40 in August - is likely to finish his career with the Patriots.
In 17 career NFL games, Patriots back-up quarterback Garoppolo, who will become a free agent at the end of the season, has completed 63 of 94 passes for 690 yards and five touchdowns with no interceptions.
The Patriots are on a bye week, which allows them extra time to now find another back-up quarterback via a trade or free agency.
Garoppolo played well while filling in during Brady's suspension related to "Deflategate" last season. The 25-year-old American completed 68.3 per cent of his passes with four touchdowns and no interceptions.
He won both of his starts before being sidelined with a shoulder injury. Garoppolo was replaced for the last two games of Brady's suspension by the Patriots' third-stringer, Jacoby Brissett.
Garoppolo is the second Brady back-up to be traded in recent months. New England sent Brissett to Indianapolis shortly before the start of the season.