Chargers' Justin Herbert does things that Philip Rivers never did, per Keenan Allen

Not many receivers in the NFL have had the luxury of transitioning from one elite quarterback to another, but Los Angeles Chargers star Keenan Allen is one of them.

Of course, Allen entered the league as a third-round pick in 2013. By that time, Philip Rivers was entering his eighth year as the Chargers' starter and already had four Pro Bowls and a Comeback Player of the Year on his resume.

Now a grizzled vet and regarded as one of the game's most polished receivers, Allen is catching passes from arguably a superior quarterback (in terms of talent) in Justin Herbert, who's set a slew of records over his first two years.

Though Allen only has two years of experience with Herbert, he's noticed a distinct difference between the 24-year-old phenom and his predecessor.

Whether it be trying to master the playbook or improving chemistry with receivers, Allen's noticed that Herbert always stays after practice to throw.

Rivers, on the other hand, called it a day once practice ended.

Per Keenan Allen, Chargers QB Philip Rivers never stayed after practice like Justin Herbert.

Allen taking a dig at Rivers should make both parties laugh. Not every quarterback has the commitment and drive to stay hours after practice throwing the rock.

Then again, Herbert might just be a different level of crazy relative to other QBs. After all, this is the same guy who's on the record saying he loves football so much that he doesn't like taking time off in the summer. Can any quarterback compete with that? Maybe Tom Brady, but the list surely isn't very lengthy.

In Rivers' defense, though, he was a 10-year vet by the time Allen joined the Chargers. Perhaps the eight-time Pro Bowler was past the point of needing extra reps.

Additionally, Rivers is a family man and had nine children to take care of. Perhaps he didn't have the luxury of being able to say after practice.

Whatever the case may be, these comments were all in good fun from Allen. We just want to see what Rivers has to say about them. Now a coach at St. Michael Catholic High in Alabama -- a program he's quietly turning around! -- Rivers might not be in touch with day-to-day proceedings at Chargers training camp.

Hopefully the 40-year-old stumbles across them eventually. Knowing his personality, he'd definitely have a witty comeback for Allen at the ready.

More importantly, Allen's Herbert praise is a great sign for the Chargers. Already an ascending talent at the game's premier position, Herbert working around the clock to perfect his craft proves he's destined to achieve greatness.