At that time, Flacco was one of the most durable quarterbacks in NFL history. Baltimore was going to the playoffs every season.
The Ravens just couldn't take that same risk this season, even though some believe Lamar Jackson can handle the No. 2 quarterback duties.
Flacco is no longer threatening Brett Favre's consecutive-games streak, battling injuries in each of his past three seasons. The Ravens aren't a perennial postseason team anymore -- they haven't made the playoffs since 2014.
Given the circumstances, the safe bet was keeping Griffin. He has more experience than Jackson, and he has been more consistent than Jackson throughout training camp and preseason games.
It was surely tempting to continue Baltimore's trend of keeping two quarterbacks after Jackson completed 64 percent of his passes and posted a 103.2 passer rating in his past two preseason games. But, if Flacco was injured again, does anyone know which Jackson the Ravens would get? Would it be the one who put up dazzling numbers at the end of the preseason, or would it be the quarterback who couldn't complete more than half of his passes in each of the first three games?
With so much riding on this season, Baltimore simply can't gamble on the most important position in the game.
Griffin was poised and efficient every time he stepped on the field. He continually moved the offense, not looking like a quarterback who was out of the league last season. He didn't get many reps throughout the entire week of practice.
"There's no doubt that you want Robert Griffin on your team," coach John Harbaugh said after Thursday's preseason finale. "He makes our quarterback room better and stronger. He looks like a starter to me. He has been a starter. Certainly a backup in this league, without question. I mean, that's not even close. I would like to have him on the team."
This didn't sound like someone trying to boost Griffin's trade value. This sounded like a coach campaigning team officials to keep the second-best quarterback on the Ravens all summer.
In the end, what did Griffin's spot really cost the Ravens? Baltimore could've kept a backup defensive lineman such as Carl Davis, a longtime special-teams ace in Albert McClellan or a former first-round pick in Breshad Perriman. The reward here is nowhere near the risk.
If nothing else, Griffin can serve as a mentor to Jackson. It was only six years ago when Griffin learned when to pull the ball down to scramble and how to protect his body when running. Call it a Heisman-to-Heisman tutoring connection.
Beyond that, there's a lot of pressure on everyone in this organization. Harbaugh is a popular name on hot-seat lists. Top Ravens officials talked all offseason how winning will fill the increasing number of empty seats at M&T Bank Stadium.
The best-case scenario for the Ravens is Flacco plays the entire season and Griffin doesn't see the field. The worst situation would've been if Flacco got hurt early in the season and the Ravens had cut Griffin.
In this instance, it's better for the Ravens to be second-guessed for keeping Griffin and not using him than not having him at all.