"I'm telling you, man, I will be ready," Hernandez said. "I've done this before on purpose so I can do it like this. I need a few games and I'll be fine."
Hernandez, who is working his way back from the bruised forearm incurred by a line drive during his first Cactus League start Feb. 26, threw an estimated 25 fastballs along with a few curveballs and changeups during a pain-free bullpen session on Tuesday. The right-hander could throw another bullpen in two days and eventually make his way back into a game this weekend.
James Paxton, who also appears to be lining up to start Opening Day, is another option for the regular-season opener March 29 against the Indians, if Hernandez is not ready.
"I'm not discarding it at all or saying [Hernandez] is not going to be ready," Mariners manager Scott Servais said. "We'll see how the bullpen goes and get him in a game again and go from there. He's had only had one outing. I don't want to get him in a big league game and only be able to throw 50 or 60 pitches. He needs to throw 75 or 80."
The Mariners entered Spring Training with a plan designed to push the 14-year veteran earlier in camp to get him ready after last season's injury-plagued campaign. There's a new plan now, and it resumes with Hernandez being re-evaluated Wednesday by the training staff.
The decision on the Opening Day starter will be made another day.
"Opening Day is a big deal to all of the players. I've never met one where it isn't," Servais said. "They all have butterflies and they should. When you don't have the butterflies or it isn't a big deal to you, then you should probably move on to your next career."
Marco Gonzales, who was removed from Monday night's 4-2 loss to the White Sox in the second inning after being hit on the right hand by a line drive, is experiencing some soreness and swelling, but might not miss a start, Servais said.
Gonzales was diagnosed with a right hand contusion.
"Contusion is an OK word. It's better than a break or a fracture," Servais said. "We got lucky. He's sore, but it's not going to stop him from keeping his arm going. Hopefully, he should be good for his next start."
Gonzales, who has put himself in position to earn the fourth spot in the starting rotation, entered Monday's game having not allowed a run in nine consecutive innings. He gave up two in the first.
Third baseman Andrew Romine was removed from the game with one out in the ninth inning after tumbling while attempting to make a play near the third-base bag. He walked off the field holding his left elbow.
Mariners starter Rob Whalen gave up one run on three hits in five innings against the Rockies on Tuesday. He walked two and struck out nine.
"I just tried to be aggressive in the strike zone," said Whalen, who is competing with Ariel Miranda for the final spot in the rotation. "I'm feeling good. I'm feeling confident with all of my pitches and I really mixed them up. I made adjustments, and that's the difference between this year and last year, when I couldn't make adjustments."
The Mariners will send Paxton to the mound as the club plays host to the Giants on Wednesday night at 6:40 p.m. PT. Dan Altavilla, Casey Lawrence, David Phelps and Mike Morin are also scheduled to pitch for the Mariners. Watch the game live on MLB.TV.