Quarterback Steve Young, the backup to Joe Montana, has agreed to a new two-year contract with the San Francisco 49ers that will make him the highest-paid reserve in the NFL.

Sources said Young, who will be 30 in October, will be paid $4.5 million over two years. Earlier, he had asked to be traded to a team for which he could start.He will be entering his fifth year with the 49ers, after two seasons with Tampa Bay and two with the Los Angeles Express of the now-defunct USFL.

Last season, Young, in relief of Montana, completed 38 of 62 passes for 427 yards and two touchdowns and scrambled for 159 yards in 15 carries. For his NFL career, he has completed 450 of 801 passes for 5,895 yards and 34 TDs and rushed for 1,317 yards and an average of nearly 6 yards per carry.

But the only time he was a full-time starter was in 1985, when he played 14 games for Tampa Bay, which traded him after taking Vinny Testaverde with the first overall draft pick.

Young's salary of $2 million for 1991 and $2.5 million for 1992 will make him the NFL's eighth-highest paid player.

All seven above him are quarterbacks.