"Prior to today's game, Eric Wedge and I met with the team so I could inform them that I have been diagnosed with cancer.
"I wanted to let you all know, as well.
"The good news is that it was caught very early, and I have great support from my wife, my family, Eric, the coaches and staff, all the players and the Mariners organization.
"I am still in the process of making some treatment decisions, but it is very possible I may have to miss some games. I do not want my absence to be a distraction to the team, which is why I am letting everyone know my situation now. Having said that, I am not ready to speak about this with the media.
"Once decisions on timing and treatment have been made, I'll be happy to talk to all of you at once. Until then, I would appreciate your patience as we all focus on baseball."
Wedge has known Datz since the two were managers in the Cleveland Indians' Minor League system in 1998. When Wedge was named the Indians manager in 2003, he brought in Datz as his third-base coach. Datz later served as the team's bench coach under Wedge from 2007-09.
"He's going to beat this. We've all experienced cancer in some way, shape or form," Wedge said. "We've been dealing with this for a couple weeks, but we feel it's the right time to announce it to the team because he is going to miss some time away from the team at some point in time."
Datz, 53, who has been the Mariners' third-base coach for the past three seasons, began his professional career in 1982 in the Houston organization. He reached the Majors briefly with Detroit in 1989.
He began coaching in the Cleveland system in 1993. He spent 2002-09 as coach with the Indians and was bench coach for Baltimore in 2010 before joining the Mariners.
"He's touched a lot of people throughout the country over the years," Wedge said. "I'm sure they're going to reach out and give him their total support. As I told him, 'You're going to beat it.' It's as simple as that. So everyone's going to do what they need to do to help him."