KANSAS CITY, Mo. - The surprising Minnesota Twins, who are in second place in the American League Central, have added a front-line starter for the second half of the season.

Right-hander Ervin Santana has been reinstated after an 80-game drug suspension and is scheduled to start Sunday against the Kansas City Royals.

"It's a little different than making a trade, I think," Twins manager Paul Molitor said Saturday. "Obviously, you're adding a good player to a club that you didn't have previous. We all knew this one was coming. It was just a matter of riding out the storm.

"The impact might be similar, but the mental part is different. It's not all of a sudden, hey, we traded for this guy. You just know you're going to have this guy available to you at some point."

Santana signed a $55 million, four-year contract with the Twins in December after going 14-10 with a 3.95 ERA last season for Atlanta. The 32-year-old tested positive for performance-enhancing drugs and sat out the first 80 games of this season.

He went 3-1 with a 1.89 ERA in spring training and was penciled in to be the Twins' No. 2 starter when MLB announced the suspension on April 3, after he tested positive for the performing enhancing substance Stanozolol.

"It was tough you know like any other bad news people get," Santana said. "Everything has been very good especially with the way we've been playing right now. We just have to keep it up and keep going."

He said he got to spend more productive time with his family during the time off. How did Santana explain his suspension to his children?

"Like every other parent would say, 'Don't do bad things' and that's it," Santana said.

Does Santana feel like he did a bad thing?

"What do you think?" he replied. "Let's leave it right there. It's in the past and I'm just moving forward. And I'm happy to be back."

Santana said "not at all" on regrets.

He went 3-0 with a 1.74 ERA in three rehab starts with Triple-A Rochester, striking out 11 in 20 2-3 innings. Santana pitched eight scoreless innings with no walks against Pawtucket on Tuesday.

"All I know, I'm ready," Santana said of his Sunday start. "I don't know if I'm going to be midseason form or full-season."

To make room for him on the roster, the Twins optioned right-hander Alex Meyer to Rochester on Saturday. Meyer had a 16.88 ERA in two relief appearances.

Santana spent his first eight seasons with the Angels and was an All-Star in 2008. He went 9-10 with a 3.24 ERA for the Royals in 2013.

Molitor said he talked to Santana to "let him know I was supportive in terms of knowing that he knows I'm interested in his well-being."

"I haven't asked him specifically about what transpired," Molitor said. "It's probably not really any of my business."

He said Trevor May, who went 4-7 with a 4.37 ERA in 15 starts, would be assigned to the bullpen with Santana now starting.