​Yahoo Sports AM is our daily newsletter that keeps you up to date on all things sports. Sign up here to get it every weekday morning.(Dillon Minshall/Yahoo Sports)Soccer’s biggest stars have shined brightest at the World Cup, but enough ink has been spilled on Messi, Mbappé, Kane, and Bellingham (for now). While nobody would be surprised if any of those players decided this week’s semifinals — kicking off today with France vs. Spain — it’s just as likely that less accomplished players will steal the spotlight.AdvertisementAdvertisementAdvertisementMeet our X-factors: Here’s one player on each of the four semifinalists who is capable of flipping an outcome and capturing eternal glory.🇪🇸 Lamine YamalBefore the tournament began, many would have expected the Barcelona wunderkind to rank among its headliners given his electric introduction at Euro 2024. It hasn’t happened yet, with just one goal and no assists through six matches, but one well-timed strike today against Les Bleus would entirely rewrite the prevailing narrative.Turning tide: Yamal entered the World Cup slowed by injury, but his Player of the Match performance in Spain’s quarterfinal victory over Belgium indicates he may be ready to erupt. As he continues playing his way into form, alarm bells will be ringing for the French defense, and what better way to celebrate his birthday — he turned 19 yesterday — than with a goal that sends his country to the World Cup Final?AdvertisementAdvertisementAdvertisement🇫🇷 Michael OliseMichael Olise is arguably the best player at this tournament without a goal, but the quiet Frenchman’s impact has been undeniable. “He saves his words,” Mbappé said of his teammate. “His feet do the talking for him.”Star wingman: Though Olise’s 17 shots have proven fruitless — the most by any player at this World Cup without scoring — the Bayern Munich winger has left his mark with a tournament-leading five assists. And given their scoring prowess, if Olise keeps putting Mbappé and Ousmane Dembélé in a position to find the net, France will be incredibly tough to beat.🏴󠁧󠁢󠁥󠁮󠁧󠁿 Dan BurnAdvertisementAdvertisementAdvertisementThe 6-foot-7 defender has registered just 24 minutes of playing time during the World Cup, but that admittedly tiny sample belies how critical Burn is to England’s success. The Three Lions’ not-so-secret weapon is deployed late in games to protect leads and patrol the air around the box, closing out victories like he’s soccer’s version of Mariano Rivera.Stat stuffer: In those 24 minutes, the high-flying Englishman has registered two blocks and nine clearances, seven of those headed. His six clearances against Mexico were the most on record by a player subbed on in the 75th minute or later of a World Cup match. And if those numbers don’t convey the type of impact he can have, perhaps these highlights will.🇦🇷 Emiliano MartínezIn his Argentine career, goalkeeper Emi Martínez has allowed goals on