After a devastating loss on Saturday night against the Kansas City Royals, the Seattle Mariners are trying to avoid a three-game sweep on Sunday. 

And if they're going to do it, they'll need better offense, but they'll also need a competitive start from veteran Luis Castillo, who has struggled for most of the season.

Castillo, 33, is 0-2 with a 6.35 ERA and has been knocked around for most of the last month. He surrendered seven earned runs in five innings against the Minnesota Twins on Monday night.

With Bryce Miller working his way back from injury and Kade Anderson dominating in the minor leagues, many fans are calling for Castillo to be moved to the bullpen - or shifted to the injured list - in the wake of his struggles.

However, ESPN's Buster Olney doesn't see that as the proper way of handling things. He made these comments to the 'Refuse to Lose' podcast on Thursday:

"You stick it out. You know, as you and I talked about a couple weeks ago, I think that this is a case where what would be worse would have be a young starter who couldn't get you through the third inning. And it wrecked your bullpen not only for that day, but also for the two days that followed.

Luis Castillo, at this point, is a good plow horse. You feel like he's going to give you a chance to get in the middle innings with a chance to win. He's going to give you some volume, and that's really important. And look, because the amount of money that he's owed, you're going to figure out the best way to use what he can give you. And until he begins to, you know, go into start, or, you know, where you feel like going into starts, that he might not make it out of the second or third inning.

And believe me, in my time covering baseball, I've seen that situation where, and we saw it with Max Scherzo with the Toronto Blue Jays recently, he was crushing the Toronto bullpen because he couldn't get through the third inning. And you're not quite at that point with Luis Castillo. And as long as the team is generally playing well, you can hang with that and hope that better days are ahead for Luis Castillo. If, at some point, his rotation spot becomes a black hole and he's not only not winning the game he's starting, but he's also crushing your bullpen, that's when you make a move."

For further discussion on Castillo, we also spoke on Friday's episode with Nick Pollack, the founder of "Pitcher List." He spoke more about Castillo's regression and what can be done about it moving forward.

The Mariners and Royals will play at 1:10 p.m. PT, and it seems quite likely that they'll have to play that game without superstar catcher Cal Raleigh, who has gone in for imaging.

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