ARLINGTON -- Mad Max is back.

At long last, the Rangers added a big-time reinforcement in their rotation, as Max Scherzer made his 2024 debut on Sunday against the Royals. The club activated the three-time Cy Young winner before Sunday's game, optioning Yerry Rodríguez to Triple-A Round Rock in a corresponding move.

Scherzer, 39, had offseason surgery to fix a herniated disc in his back and then dealt with thumb soreness and nerve inflammation that further delayed his return to the mound. But ever the competitor, Scherzer has been anxious to get back on the mound.

"I'm just champing at the bit to get out there," Scherzer said. "I've been doing this for six weeks now. It's extremely frustrating, but I got to turn the page. That's the hand I've been dealt. Now I've got a chance to go out there and just want to go out there and help the team win."

Entering his 17th season, Scherzer acknowledged how difficult the last two months have been. He was originally ahead of schedule following back surgery and could have made a return in mid-May before the nerve issues in his thumb cropped up.

"I aced the rehab on the back surgery," Scherzer said. "I haven't had any symptoms coming from the back surgery in over two months. I thought if I did the rehab right, I'd be back out here pitching. So I never, to use your words, thought about my pitching mortality because of the back surgery, but when you're dealing with nerve stuff, yeah, you definitely do think about your pitching mortality. This nerve stuff could mean long term damage and what it does to your arm. When you're dealing with this, bad things can happen."

The Rangers have been cautious with Scherzer's rehab, especially due to a loss of grip strength following his last rehab start.

He has made three rehab starts; in his most recent one on June 15, he struck out eight batters in 4 2/3 innings for Triple-A Round Rock, allowing three runs on four hits with two walks. His fastball topped out at 93.4 mph and averaged 92.1 mph, slightly less than in his previous outing, and down from his 2023 average of 93.7 mph.

Scherzer said he's not worried about a loss of velocity and feels it will be normal come Sunday afternoon.

"I'm an adrenaline pitcher," Scherzer said. "You put me in the right atmosphere and I'll pitch in it. I don't bring my absolute best in situations that don't require it. So, I've never been one to throw my best bolts in the bullpen. I'm always lagged in that. Even in Spring Training, I'd be kind of down [velocity-wise]. It's not a cause for concern yet. I don't think anything of it."

Scherzer threw 79 pitches in his final rehab start, a shade over the target of 70-75. Manager Bruce Bochy said there's no set pitch count for his season debut, but they'll see how the game goes.

"I'll just kind of wait and see," Scherzer said. "I'll just navigate it how it needs to be navigated."

Scherzer was acquired from the Mets at last season's Trade Deadline. Scherzer made eight starts for Texas in 2023, going 4-2 with a 3.20 ERA and a 53/15 strikeout-to-walk ratio in 45 innings. He started one game in the World Series, allowing zero runs in three innings.

Bochy said Dane Dunning will go to the bullpen now with Scherzer's activation on Sunday. The Rangers' rotation now is Scherzer, Nathan Eovaldi, Michael Lorenzen, Jon Gray and Andrew Heaney. Jacob deGrom and Tyler Mahle continue to rehab from their respective Tommy John surgeries, eyeing a return around the Trade Deadline.

Cody Bradford, who started the season in the rotation, is likely headed to the bullpen when he returns from a stress fracture on his rib.

"I'm excited about [Scherzer's return]," Bochy said. "I know he is too. … This really makes us a better staff. We saw it last year when guys went down there to help out. It really helps that the bullpen can eat, not just innings, but quality innings. Dane is so good about that. We saw what a difference he made when he helped us in the bullpen."