By Andrew Gastelum The midfielder is out of contract with Atlético Madrid at the end of this season. View the original article to see embedded media. Atlético Madrid and Mexico midfielder Héctor Herrera will reportedly join MLS side Houston Dynamo this summer, according to TUDN’s Luis Omar Tapia. Herrera will be out of contract at Atlético at the end of this season, making him available on a free transfer. Tapia reported that the midfielder will sign a five-year contract. Per MLSSoccer.com, Houston will make Herrera a Designated Player. Herrera, 31, has made 71 appearances since arriving at At…