COSTA MESA, Calif. (AP) When Los Angeles Chargers receiver Tyrell Williams gets an opportunity, he makes the most of it.
It was true of his breakout season last year, when he had 69 receptions for 1,059 yards and seven touchdowns. It was true of his collegiate career at Western Oregon, attending the Division II program instead of walking on at Oregon State. And it was certainly true of his unlikely route to the Beavers' pro day in 2015.
Williams finally got to catch up with Los Angeles Rams quarterback Sean Mannion, who helped launch his unlikely NFL career because the former Oregon State standout needed someone to catch passes two years ago, after their teams held a joint practice on Saturday.
''It was good to see him and just kind of reminisce,'' Williams said. ''I hadn't seen him since the pro day, really.''
Oregon State didn't have any draft-eligible receivers that Mannion could work out with in front of league executives, coaches and scouts that year, so Williams' agent reached out with the suggestion that his client could be a target for the four-year starter. In return, Williams would get a chance to showcase himself in front of the massive crowd Mannion would bring to Corvallis, Ore.
The arrangement proved beneficial for both. After a few weeks of working out together, Mannion went through his scripted throws, helping convince the Rams to select him in the third round.
Treating it like a ''track meet,'' Williams showed off his athleticism, including running a sub-4.5 40-yard dash. The chemistry he and Mannion had quickly developed allowed Williams to ignore the pressure of the moment.
''We felt comfortable with each other and just went out there and had fun,'' Williams said.
Williams signed with the Chargers as an undrafted free agent, and stepped up with three 100-yard games last season after starter Keenan Allen suffered a season-ending knee injury. The speed Williams showed at the pro day was even more evident on the field, making six receptions of at least 40 yards. He was a devastating option working out of the slot.
After playing with two future NFL wide receivers at Oregon State in Brandin Cooks and Markus Wheaton known for similar game-breaking burst, Mannion wasn't shocked that Williams produced when he got the chance.
''Tyrell I think is one of those long striders. Real top-end speed, like those others guys in a lot of ways,'' Mannion said. ''I got to see his talent first-hand so it wasn't that surprising to me. I knew kind of with the injury situation there he was going to get some chances and he clearly capitalized on it.''
With first-round pick Mike Williams out because of a back injury that could sideline him for the season and Allen limited due to a sore calf muscle, Williams is getting more work in training camp to refine his skill set. At 6-foot-4, he wants to improve at catching and contesting jump balls, an issue that was evident during practice Monday.
Williams also wants to use his reputation as a burner to confuse and challenge opposing defensive backs.
''I'm trying to be able to control my speed and use it as deceptively as I can because guys know I'm fast so I can kind of temper that a little bit and attack them at that or vice versa,'' Williams said.
Fellow Chargers receiver Isaiah Burse said Williams has only scratched the surface of how he can exploit that explosiveness.
''He still kills everybody but you don't understand how unstoppable you can be if you just use your speed to its full potential every single rep. Dudes are already scared of him, and they are going to be that much (more) scared,'' Burse said.
''He's got to continue to pound that in his head. Your speed, use your speed, use your speed. And I feel like he's starting to get it. Dude, he's fun to watch.''
Williams might have finished 17th in the NFL in yards receiving last season, but he is going into every day with the same scrappy mindset that earned a roster spot in the first place.
''I still feel like I'm still fighting as being an undrafted guy,'' Williams said.
Mannion won't take any credit for his part in facilitating the emergence of Williams. To hear him tell it, Mannion was as much the fortunate beneficiary as Williams.
''Shoot, he's an awesome, awesome player,'' Mannion said. ''But it was funny the way it worked out where I went from having nobody to throw to really at my pro day - at least not at wide receiver - to having Tyrell, who is now one of the top guys on the Chargers. To have him at my pro day made it easy.''