Marcus Mariota faces a pivotal season in 2019 — one that could prove to be the most important of his career.
In his time with the Titans we have seen some major ups, and some major downs. Mariota has faced a ton of criticism, some fair, some not.
He’s has dealt with a lot of adversity since being drafted by the Titans partially due to injuries, and partially due to a drastic number of coaching changes.
But, in 2019, Mariota has a few luxuries he hasn’t gotten to enjoy over the past years. He has continuity with the coaching staff, chemistry built up with multiple players around him and he’s spent the offseason gaining weight to avoid injury.
But there’s another factor that plays into this many are overlooking.
Most experts believe it takes five years for a quarterback coming out of college to adjust and mature to the NFL. While this can’t be proven or disproven, there are some numbers back it up.
Here’s a look at some other quarterbacks who took a leap in their fifth year.
Cam Newton

Newton’s fifth year came in 2015.
That year, the Panthers finished the season 15-1 and went to the Super Bowl. In the previous season, the Panthers only managed a 5-8-1 overall record.
In 2015, he threw for 35 touchdowns — the most he completed before that came in 2013, when he threw 24.
Newton also only committed 10 interceptions. Before that, his fewest interceptions in a season came in 2012 and 2014, when he threw 12.
It would be foolish to think a player can drastically change all of his stats from his first four years. Newton’s yards and completion percentage stayed fairly similar to years past in 2015.
But, improving his touchdown-to-interception ratio and leading his team to a near perfect season cemented Newton’s place as a franchise quarterback.
Matt Ryan

Ryan’s fifth season came in 2012.
Unlike Newton, Ryan seemed to have improved everything but his interception numbers that year. He also led the Falcons to a 13-3 record.
Ryan completed 68.6% of his passes, which was an improvement over his previous best when 62.5% in 2010. The 4,719 yards threw for were more than his previous best total that came in 2011 when he passed for 4,177 yards.
His 32 touchdowns were also the most he ever had in a season to that point.
Andrew Luck

Luck’s numbers are a little more tricky to pinpoint, and they were all over the place in his first four seasons. Judging by stats alone, Luck’s fifth year is the year he found consistency.
Luck’s 63.5% completions was the most of his career to that point, and his 32 touchdowns ranks only second to his third year in which he threw for 40 touchdowns. While the 13 interceptions he threw doesn’t rank as his fewest, that year saw the best touchdown-to-interception ratio of his career.
Drew Brees

Titans fans love to compare Mariota to Brees, and there are a lot of similarities in the early phases of their careers.
Both threw more interceptions than touchdowns in their third seasons (Mariota 13-14, Brees 11-15). Both threw for around 3,000 yards each of their first three seasons, and both had to deal with being on inconsistent teams.
Now, Brees has gone on to win a Super Bowl, appear in 12 Pro Bowls, and is a First-Team All-Pro selection.
Brees also holds many NFL records, including the highest completion percentage in a season at 74.4%, which he broke his own record of 72% from the previous.
He also owns the record of most consecutive seasons with at least 4,500 passing yards, and is the all-time leader for passing yards.
Others

Andy Dalton, Eli Manning, and Philip Rivers also had their careers take off in year five.
However, as mentioned before, this is not a proven fact: Russell Wilson, Tom Brady, Joe Flacco, and Ben Roethisberger’s numbers stayed mostly the same, or even took a slight dip in their fifth seasons.
Conclusion

It would be irresponsible for Titans not to franchise tag or sign Mariota to a short-term deal if he has a decent year in 2019.
Given all the factors, Mariota should have a big season in 2019, or at the very least find the magic he had before all the injuries and coaching staff changes set him back.