No baseball on Earth could hit harder than the news Doug Davis received three days ago. On Friday, the Diamondbacks announced that their left-handed pitcher has been diagnosed with thyroid cancer.

Davis went in for a routine physical on Feb. 6, where a lump was found in his throat.

Biopsy results on Wednesday confirmed the news. He will have surgery on April 10 and be out an expected 4-6 weeks.

“I know I’m not alone,” Davis said. “I’ve got all the help in the world, and I’m definitely optimistic of the outcome.”

The prognosis for a full recovery is good. Team doctor Michael Lee said Davis will be home the day after the surgery.

“It’s very straightforward,” Lee said. “If he wasn’t a pitcher, he’d be back to normal duties and activities of daily living very quickly. Because of the exertion that he puts out in his job and his requirement, it’s going to be a bit longer.”

Davis said his mother had the same cancer and made a full recovery, and his sister had her thyroid removed as well.

“Doug has beaten a lot of things in his life. ... This is probably the worst, but he has come back,” Doug’s father, Mike Davis, said. “He has a great mind-set. He wants to start. He wants to do his job. He is very set on this.”

Davis pitched Friday in an exhibition game against Colorado and plans to make his first two starts of the season. His first start will be April 3 against Cincinnati and his second will be April 8 at Los Angeles.

Davis elected not to have the surgery immediately.

“If you know Doug, it doesn’t surprise you (that he would make the starts),” Diamondbacks manager Bob Melvin said. “We were just trying to get over the fact that this was happening, and he’s talking about his starts.”

Davis fared poorly against the Rockies — giving up eight runs in 2 2/3 innings — but he said playing the game helps keep his mind off the cancer.

“It’s somewhere to get away and not stress about something that’s going to take me down for a while — but not out for good,” Davis said.

Davis, 32, set a career high with 13 victories last season, his first with the D-Backs.

The team was told of the news at dinner Thursday.

“All of us are there with him in his corner,” closer Brandon Lyon said.

Melvin said he isn’t sure who will replace Davis in the rotation after the surgery. The timetable for Randy Johnson’s return is in that range, so it’s possible he could slip into the spot fairly quickly.

Yusmeiro Petit could also be a stopgap. He filled in for Johnson as a starter at times last season.

“We’ll go out there and do our job, but we understand what he’s taking on is a lot more than what we’re dealing with on the baseball field,” Melvin said.