An NFL roster is never set in stone.

In fact, all 32 teams are constantly updating and tweaking it throughout the year.

Nonetheless, Saturday is an all-important day as every team must trim their rosters down to the mandatory 53-man limit. All in all, 1,184 players are now out of a job as of 1:00pm PT.

For that reason, it's worth celebrating the ultimate underdogs who made the Chargers' initial 53-man roster.

Everyone knows the Bolts have the league's richest history when it comes to undrafted free agents not only making the team, but making a tangible impact. This year, three players defied the odds in CB Brandon Facyson, WR JJ Jones and RB Detrez Newsome. That makes it a remarkable 22 years in a row that an undrafted player made the Chargers' 53-man roster, by far the longest streak in the NFL.

Even so, it bears repeating once again how often rosters change.

In fact, it's likely the Bolts' 53-man roster will change in the coming days due to waiver claims and possible free agent signings. In fact, the Bolts made several roster claims and signings each of the past two years in the 24-48 hours after announcing the initial 53-man roster.

Still, the undrafted free agents who made the roster on Saturday have a lot to be proud of after turning heads throughout the summer.

The 6-2, 197-pound Facyson is a tall cornerback with ideal length. In addition to a strong training camp, he had blanket coverage throughout the preseason, finishing with a pair of passes defensed as well as an interception. The Virginia Tech product started 47 of 55 career games for the Hookies, amassing 131 tackles, nine tackles for loss, 44 passes defensed, five interceptions and three forced fumbles.

Meanwhile, Jones made quite the impression as a returner during the preseason. The speedster showed off his 4.2 speed on several occasions, most notably his electric 72-yard punt return to the house against the Seattle Seahawks. Overall, he averaged 12.6 yards on seven punt returns and 22.8 yards on six kickoff returns. The Chargers added the 5-10, 173-pound wideout after he emerged as a big-play weapon for West Georgia. He had a catch of at least 25 yards in four games in 2017, though he made most of his impact on special teams.

Finally, Newsome made the most of his opportunities this preseason, leading the team in carries (42), rushing yards (159) and touchdowns (two). He also proved to be a receiving threat, leading the Bolts with 10 catches. The Chargers initially signed the 5-10, 210-pound running back after a standout career at Western Carolina as his 6,969 all-purpose yards are the most in school history. Newsome ranks second in school history in career rushing yards (3,728), rushing touchdowns (37) and 100-yard rushing games (16). In 2017 he became the first Catamount to eclipse 1,000 yards rushing for three straight seasons. Newsome is also the school's all-time leader with 46 total TDs, adding seven additional touchdowns through the air and a pair via kickoff returns.

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