Adam Schefter reacts to the news that Philip Rivers will enter free agency this year, officially ending his 16-year run with the Chargers. (0:59)

COSTA MESA, Calif. -- Asked if Philip Rivers still can play quarterback in the NFL, Los Angeles Chargers receiver Keenan Allen did not hesitate to back the only starting signal-caller he's ever played with.

"He comes to work every day still the same way," Allen said. "You never question his work ethic. You never question his passion on the field. His energy is always there, and he can still make the throws."

Of course, Allen won't get a chance to see if his statement become a reality, as Rivers and the Chargers mutually agreed to part ways Monday. Rivers will become a free agent in March, and he has been adamant that he wants to play football in 2020.

Certainly, Rivers earned a reputation as one of the best trash talkers in the league. But his toughness, ultra-competitive nature and accuracy also set him apart, making him the most prolific quarterback to ever wear the royal blue and gold.

Some important statistics of the Rivers era include:

A 224-game consecutive starts streak, making him the active leader in the NFL.

A franchise-record 59,271 passing yards and 397 passing touchdowns.

Rivers owns more than 30 franchise records, and in 2014 he became the first player in league history to post five straight games with a passer rating of at least 120 in a single season.

Eight Pro Bowls, tying Rivers with Antonio Gates for the second-most Pro Bowls by a Chargers player since the 1970 NFL-AFL merger, trailing only Junior Seau's 12 selections.

Rivers' 70 games of 300-plus yards passing are good enough for fourth in NFL history behind only Drew Brees, Peyton Manning and Tom Brady.

His 123 career regular-season victories as a starter rank ninth in NFL history.

Rivers was named the 2013 NFL Comeback Player of the Year.

Rivers was a 2011 Walter Payton Man of the Year finalist for his work with the Rivers of Hope Foundation that raised more than $1 million to help abandoned and orphaned children.

Here are the top five highlights of Rivers' illustrious 16-year career with the Chargers:

No. 5: Rivers throws for a career-high 503 yards vs. Green Bay Packers, 2015

Rivers finished with career highs in pass attempts (65), completions (43) and passing yards (503) in a Week 6 contest against the Packers, marking the first 500-yard passing performance in team history. The Chargers failed to convert on fourth down near the goal line, losing 27-20 at Lambeau Field, but this game was a great illustration of the precision passing that became Rivers' calling card.

No. 4: First career start in 2006 against the Oakland Raiders

Rivers completed just 8 of 11 passes for 108 yards in his first career win, a 27-0 victory over the Raiders on Sept. 11, 2006. However, his lone touchdown was a 4-yard pass to Gates, the beginning of the most prolific quarterback-tight end tandem in NFL history. The two combined for a league-record 89 touchdowns. Gates announced his retirement earlier this year.

No. 3: Rivers leads Chargers to comeback victory vs. Kansas City Chiefs in 2018

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Down 14 points with 7:55 left at Arrowhead Stadium, Rivers led the Chargers to two fourth-quarter touchdown drives and won the game with a completion to a wide-open Mike Williams on a two-point conversion to end the game. This game is a good example of a resilient Rivers at his best, as he struggled early on but finished with 313 passing yards, two touchdown passes and two interceptions. Rivers recorded 27 fourth-quarter comeback wins during his time with the Chargers, tied for 13th in the NFL.

No. 2: Rivers leads Chargers to win in Eli Manning's return to San Diego in 2013

Known as the "ShEli" game, Manning's spurning of the Chargers in the 2004 draft served as a backdrop. With Chargers fans booing Manning every chance they got, Rivers was surgical, completing 21 of 28 passes for 249 yards, with three touchdowns and no interceptions. Rivers' efficient play allowed the Chargers to race to a 24-0 lead and never look back, cruising to a 37-14 victory on Dec. 8, 2013. The win was part of a strong finish for the Chargers, as they won five of their last six games to reach the postseason. Rivers finished with a 3-0 record against Eli Manning.

No. 1: 2007 AFC Championship Game in which Rivers played with a torn ACL

The most notable thing Rivers is known for is his toughness, and that was on display on Jan. 20, 2008, when Rivers played just six days after suffering a torn ACL and meniscus in his right knee, which I detailed here. Although the Chargers lost 21-12, Rivers limping through the game sealed his status as one of the toughest players the league has seen.