According to Kyle Shanahan, Trey Lance will play, "When I think he gives the team the best chance to win."
That may be sooner rather than later.
Lance has played well in camp according to reports (13-14 in practice on Tuesday) while Garoppolo is the same quarterback.
With all of Kyle Shanahan's previous experience with great dynamic offenses, with Robert Griffin III and Matt Ryan, Trey Lance will add a new dynamic to the 49ers offense.
Red Zone Offense
Kyle Shanahan's Red Zone Efficiency (Touchdowns Only) as a Head Coach or Offensive Coordinator:
2020 San Francisco - 67% (7th in the NFL)
2019 San Francisco - 55% (20th in the NFL)
2018 San Francisco - 41% (32nd in the NFL)
2017 San Francisco - 47% (27th in the NFL)
2016 Atlanta - 64% (8th in the NFL)
2015 Atlanta - 54% (18th in the NFL)
2014 Cleveland - 48% (24th in the NFL)
2013 Washington - 52% (21st in the NFL)
2012 Washington - 61% (4th in the NFL)
2011 Washington - 41% (29th in the NFL)
2010 Washington - 51% (21st in the NFL)
2009 Houston - 52% (13th in the NFL)
2008 Houston - 45% (26th in the NFL)
His best three seasons were last year when the team threw the ball 59% of the time (in 2019 they threw 49%). They were constantly playing catchup and scoring touchdowns that would only make the final box score closer.
The other two seasons Shanahan had Robert Griffin III and Matt Ryan. In 2012, Griffin scored 15 of his 27 total touchdowns in the red zone. A huge part of that was utilizing RG3's rushing ability to score and as a threat to make the rest of the offense better.
With the Flacons, Ryan and Shanahan were dicing up defenses with a deadly play-action and one of the league's most potent offense's ever.
They scored a league high 540 points tying the 2000 Rams for seventh most in an NFL season. They were 71 points ahead of the team in second and accumulated 171 points above the league average.
In that 2016 season, Ryan threw the third-most Red Zone touchdowns (23 TDs) behind only Drew Brees and Aaron Rodgers.
In 2019, Shanahan and the 49ers ran for 2,303 yards, second only to the Lamar Jackson led Ravens, who were historic. They also scored the most rushing touchdowns of any team in the NFL.
In 2012, Shanahan had a similarly explosive rushing attack finishing first in the league in rushing yards, and second in rushing touchdowns.
In 2019 and 2012, the 49ers and Washington Football team both ran the ball 51% of the time.
When Shanahan and Griffin were paired, they destroyed and surprised defenses with the zone read. In 2018, he doubled down on how effective it was in the NFL.
Lance has been running those same zone-read concepts in the 49ers training camp so far. It will be a huge part of the 49ers offense when he takes over and it will only make the 49ers passing attack more deadly.
During 16 games in 2019 at North Dakota State, Lance ran for 1,100 rushing yards and 14 rushing touchdowns while averaging 6.5 yards per attempt.
Shanahan's offense on the ground was already successful enough in 2019, without the added element of a quarterback who makes football 11-on-11 in the run game.
While Shanahan was able to bring the 49ers to new heights in 2019, the change to Trey Lance will supercharge the best aspect of the 49ers.
That will also make the 49ers passing offense better as well as in 2012 when Shanahan broke and still holds the record for play-action yards in a season. When he had a quarterback who could also add a rushing element, it made life easier for everyone.
When will the 49ers start Lance? It's hard to predict. But once they do, he will fundamentally change the 49ers offense for the better. This is Shanahan's legacy.