ポトマック・ナショナルズ
In 2007, Estrada pitched for the GCL Nationals, the Class-A Hagerstown Suns of the South Atlantic League, and the Advanced-A Potomac Nationals of the Carolina League. He logged innings in 23 starts, winning 6, losing 8, and recording a 4.85 ERA with 102 strikeouts and 37 walks.