There has been a bright light shining on every move Antonio Brown makes throughout Raiders training camp, and the HBO documentary series has done its best job to highlight the star receiver in this season's edition of Hard Knocks. While fans have an obvious fascination with the All-Pro wideout—from his outspoken personality, the extreme frostbite on his feet and his ongoing helmet drama—Episode Four focused its attention on another receiver who is constantly turning heads and making a name for himself. 

Keelan Doss, an undrafted rookie out of UC Davis, has been one of the more impressive additions to Oakland's roster this summer. He's making the best of his opportunities when the ball is thrown in his direction, giving the Raiders' offense an unexpected boost in the preseason. Raiders coach Jon Gruden is falling in love with the rookie receiver. He's heard saying, "Man, I like this Doss kid" and "I want to see more of Keelan Doss" on numerous occasions throughout the episode. The 23-year-old leads the Raiders with 11 receptions for 99 yards and a touchdown in three games, and he's been a go-to target for Nathan Peterman, who's jockeying with Mike Glennon for the backup quarterback spot. 

In the Raiders' third preseason affair against the Green Bay Packers, which was played on an 80-yard field in Winnipeg, Peterman led the team downfield on a game-winning drive and received an endless amount of praise from the players and coaching staff in the locker room. Gruden approaches Peterman following the game and says, "That's as good as I've seen you play since Pitt, man." 

The third-year quarterback, who experienced his fair share of struggles with the Buffalo Bills during his first two NFL seasons, has made the backup QB decision a tough one for the Raiders. Will they keep three quarterbacks? Or will they choose to go with the former Pittsburgh Panther over Glennon? It's definitely a storyline to keep a close eye on in the season finale, which will air Tuesday, Sept. 3—two days before the NFL regular season kicks off. 

A feel-good story from Episode Four

Jason Cabinda, who is of Cameroon descent, was shown Facetiming his mom when he surprised her with a ticket to the preseason game in Canada. Her eyes instantly lit up and she screamed to the top of her lungs in excitement. All Cabinda could do was smile, and I'm sure it caused viewers to do the same. Her response: "Thank you so much, this made my day," a statement anyone—athlete or not—would like to hear from their parent. 

The second-year linebacker from Penn State was cut during Raiders training camp last year around this time, but found himself back on the roster midway through the 2018 season, appearing in 10 games and racking up 21 tackles. However, he's fighting for a spot once again. He had some high moments throughout the game vs. the Packers, especially in the second half. And his mom was in the crowd looking as proud as ever. 

Luke Willson gives Drake props 

The Raiders tight end, who is originally from Canada, was ecstatic about going to play in his home country for the first time. He was pumped at practice, getting his teammates and fellow tight ends fired up to sing the Canadian national anthem, 'O Canada'. 

There was a moment when he was asked by a member of the Raiders' coaching staff whether he thinks Drake or Mike Myers held more weight in Canada, and Willson responded by saying Drake, without much hesitation. He went on to say Drake and Wayne Gretzky were neck and neck as most popular Canadians, but gave the slight edge to Aubrey Graham due to the Raptors' NBA title. 

More rookie karaoke moments

Hunter Renfrow had his turn, now it was Doss's chance to get up in front of the team and sing. His song of choice: "My Girl" by the Temptations—a good pick if I may say so myself. He was followed by Johnathan Abram, who went with "U Got It Bad" by Usher. To be such a hard-nosed safety, his performance wasn't too bad. It even forced Gruden to crack a smile.

But the song that stood out most in Episode Four was "Knock On Wood If You're With Me," a remixed version of Gruden's frequent remark every time he wants the team to show unity by knocking on a piece of wood if they agree with a statement of his. Well done, HBO. It even caused me to nod my head a bit.