Richie Martin will have to wait a little while before beginning his first full Minor League season.

The A's fourth-ranked prospect will miss six weeks after undergoing surgery to repair his left medial meniscus, according to the San Francisco Chronicle.

Martin, a 21-year-old shortstop, injured the knee while sliding, the Oakland Tribune reported, and will begin the year on the disabled list.

Selected 20th overall in last year's Draft out of the University of Florida, he was regarded as one of the top defensive shortstops in his class and posted a .948 fielding percentage in 46 games with Class A Short Season Vermont last summer.

This spring, Martin committed one error in 16 innings with the Major League club and went 0-for-5 with a walk and three strikeouts in five Cactus League games. He's expected to begin the season with Class A Advanced Stockton.