Cowboys’ Zack Martin gets $40M guaranteed in new six-year deal

FRISCO, Texas — Locking up a priority to keep since last summer, the Dallas Cowboys have agreed to a six-year extension worth $84 million, including $40 million guaranteed, with All-Pro right guard Zack Martin, a source told ESPN’s Adam Schefter. The deal, which runs through 2024, includes a $20 million signing bonus, a source told ESPN. Martin skipped the organized team activities without the security of the long-term contract, but he will attend the first two days of the mandatory minicamp after progress was made last weekend in the negotiations. The Cowboys had hoped to lock down Martin to a long-term deal during training camp last year, but the talks never ventured very far. Once the season began, Martin put the negotiations on hold but he said he never wanted to leave the Cowboys. The talks began anew early in the offseason and the sides were close to a deal about a month ago before hitting a snag. Those issues were resolved in the past few…