Colorado Rockies pitcher Chad Bettis has been receiving a tremendous amount of support as he begins chemotherapy on Monday.

At the beginning of March, Bettis and the Colorado Rockies announced his testicular cancer had returned and he would be undergoing chemotherapy.

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Monday, the Rockies tweeted that those treatments had begun.

They also asked fans to reach out and how their support to Bettis and his family by using the hashtag TogetherForBettis.

Not only have hundreds of Rockies fans responded, teams and players across Major League Baseball and more have reached out to wish him the best.

We're pulling for you, Chad. Get better soon! #TogetherForBettis @Cubs @Reds

— Cleveland Indians (@Indians) March 21, 2017

Bettis and his wife Kristina are expecting their first child, a baby girl, this month.

He had originally been diagnosed with testicular cancer in November and had surgery on Nov. 29.