Per Club and MLS policy, terms of the deal were not disclosed. Earnshaw will be added to the Fire roster upon receipt of his P1 Visa and International Transfer Certificate.
"Robert is a veteran player with a wealth of international experience," said Fire head coach and Director of Soccer Frank Yallop. "He's a gifted, natural goal-scorer who is already familiar with the League, and we're glad to have him join the Fire as we continue the second half of the MLS campaign."
The Welsh international joined Toronto FC prior to the start of the 2013 season. In 26 MLS matches, Earnshaw scored eight goals, including a brace in just his second appearance with the club in a 2-1 win over Sporting Kansas City on March 9.
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