LOS ANGELES, CA - OCTOBER 26: Manny Machado #8 of the Los Angeles Dodgers hits a sixth inning single off the wall against the Boston Red Sox in Game Three of the 2018 World Series at Dodger Stadium on October 26, 2018 in Los Angeles, California. (Photo by Ezra Shaw/Getty Images)

MLB star Manny Machado has made US sports history in signing the most lucrative free agent contract ever.

Machado inked a ten-year contract with the San Diego Padres worth $USD300 million ($AUD420 million).

The 26-year-old is a four-time All-Star and has overtaken Alex Rodriguez's $USD275 million for the free agent contract record.

He sits behind only Giancarlo Stanton's 2014 $USD325 million extension with the Miami Marlins for the biggest contract ever signed in US professional sport.