The promo for the MLB Network documentary “Junior” — which will feature Hall of Fame outfielder Ken Griffey Jr. — comes with a ringing endorsement from LeBron James. “He makes the game of baseball cool,” James says. Ditto with Mahomes 30 years from now. He might not hold the sports world quite like James or Tom Brady, who is the only player who sells more jerseys. Yet given Mahomes has a NFL MVP and Super Bowl MVP award with his name on it before turning 25 – he has been able to capture the imagination of those who follow him. There is nothing cooler than that. Griffey Jr was all of that. The sweet left-handed swing. The wall-climbing catches. The backwards hat. For a generation of 90s baseball fan, Griffey Jr was the coolest athlete in all of sports. Griffey Jr.’s 1989 UpperDeck rookie card was the grail for a generation of collectors. While James might be this generation’s Michael Jordan, Griffey’s iconic match is evolving in another sport in the present day. Think Kansas City’s Patrick Mahomes II. To understand Griffey and just how cool he was, the younger generation should draw the comparisons with Mahomes. The smile Sometimes it starts with the smile. Griffey’s smile alone showed a youthfulness that engulfed baseball at the right time. “The Kid” hit 19 homers as a rookie in 1989, and by 1990 he was hitting between Cal Ripken Jr and Mark McGwire in the All-Star game. Mahomes, meanwhile has become a meme machine with his smile and “froggish” voice, but his rise with the Chiefs is undeniable. He threw 50 TDs in 2018 and led Kansas City to a Super Bowl championship the following seasons. Grand entrance Griffey played his first five career games on the road, but his debut in the Kingdome with the Mariners was memorable. He hit a home run off Chicago’s Eric King on the first swing. Mahomes did not take long to make an impact as a first-time starter in 2018. He threw for four TDs in his first start that season against the Chargers – then followed that up with a six-TD performance against the Steelers. Style In the 1990s, kids wanted to be Junior. How many times did you try to replicate that swing in the backyard – even if it was impossible? Whether it was a shallow fly ball in center or full-speed leaping catch at the wall, Griffey Jr became the ultimate highlight-reel centerfield. Of course, you had to wear your hat backwards like Griffey did when he won the Home Run Derby in 1994, 1998 and 1999. Mahomes, meanwhile, is part of a full-scale evolution at the quarterback position. Mahomes can run, but it’s that laser arm – one cultivated through baseball, of course – that helped the Chiefs after 35.3 points per games in 2018. It’s more than that, however. Simply go out in the backyard and play back-yard football with your kid and his friends. How long will it take for the first no-look pass? Father-son relationship Griffey had the unique opportunity to play with his father Ken, and the tandem made history by hitting back-to-back homers on Sept. 14, 1990. Junior even had time to steal a catch from his father from time to time. Mahomes, meanwhile, is the son former pitcher Pat Mahomes, who enjoyed a serviceable career from 1992-2003. The father-son duo famously embraced in the immediate aftermath of Super Bowl LIV after Mahomes II led a fourth-quarter comeback in a 31-20 victory. Cool factor Does the comparison fit? For 1990s kids, Junior was that guy – and baseball was still at the forefront of the national consciousness. Jordan, Joe Montana and Wayne Gretzky were more dominant in their sports, but they weren’t The Kid. Every kid wanted to be Junior – and 30 years later that swing, those catches, that hat – and yes, that elusive UpperDeck card — will rush back with this documentary. You had to have that Mariners hat in 1993. Hey, that’s why you cheered for him.