He'd still like the ball over Tyson Ross, though. The competitive streak in the 34-year-old right-hander doesn't allow for anything else.
"I've been in this situation before," Shields said Saturday. "I think in 2011, David Price [in Tampa Bay] took my Opening Day start after three years. And I got it right back the next year."
Shields then smiled. He may be low-key in the clubhouse, but on the mound he's a "bulldog," as described by teammate Casey Janssen.
When Mark Buehrle just missed reaching 200 innings last year to end a 14-year streak, Shields' nine-straight 200-inning seasons became the longest in baseball.
"I pride myself going deep in games and just posting every five days," he said.
Shields did that in his first season in San Diego in 2015 that began with his seventh career Opening Day start.
But his numbers were down. He allowed 33 homers, tied for the most in the majors. His 81 walks were the most in his career. He finished 13-7 with a 3.91 ERA for a team that went 74-88.
Rookie manager Andy Green, who said he's spent a lot of time "listening" to the talkative Shields in the offseason, wants him to pitch inside more.
"That was something from the start we looked at and emphasized with him, 'Hey, you've got to get in on lefties and make your changeup play better,' " Green said. "I think that's the bulk of where his problem was last year, pitch mix, pitch location."
Shields wasn't alone in his struggles as the remade, high-priced team won 74 games. Shields said it's clear the 2015 Padres lacked chemistry.
"I think bringing in 11 guys last year was a little difficult as far as the comfortability part," he said.
Shields believes Green is key to creating a better atmosphere. Shields had high praise for his manager even after he announced on the first day of spring training that the 28-year-old Ross would start the April 4 opener against the Los Angeles Dodgers.
Shields will get the ball the next day.
"He handled it like a pro," Green said of Shields. "And he told Tyson, 'Hey, it's your job this year, but I'm coming back for it next year.' That's what you want to hear."
Shields, entering the second year of a four-year, $75 million contract, is confident he has plenty left at age 34.
"He's a bulldog out there," Janssen said. "That goes hand in hand with all those innings that he does pitch."
Shields is entering the point of his career where many starting pitchers drop off in production. He's also been mentioned in trade talks, and could be a candidate to be dealt at the trade deadline if the Padres are out of contention again.
It won't change Shields' routine. With Buehrle unsigned, Shields might be baseball's best bet to be on the mound every five days.
"I just try to do as much as I can to take care of my body in between starts and, obviously, in the offseason have a good workout program," Shields said. "But with that said, definitely good luck is on my side. I've been very fortunate to stay healthy and stay intact."
Closer Fernando Rodney and reliever Kevin Quackenbush, both recovering from hamstring injuries, threw their first side sessions of camp Friday. "They both felt really good," Green said. ... LHP Buddy Baumann was sent to San Diego to get his troublesome back examined.