The 19-year-old has become an important player for the Czech Republic outfit this season, scoring four goals and providing eight assists in 21 appearances across all competitions.
The Hammers are now prepared to step up their interest in the striker ahead of the winter window, but they could face stern competition from other Premier League clubs including Liverpool, who are also keeping tabs on the teenager.
Hlozek is one of the brightest prospects to have come from the Czech Republic in recent years and has already made 12 international appearances, including four at Euro 2020.
The striker has played 106 times for Sparta Prague since making his senior debut in 2018, scoring 32 goals and registering 29 assists. body check tags ::