Daniel Norris submitted a handwritten paper to stay in the Tigers' rotation in August and September as his innings limit neared, and it worked.

“I heard that I had an innings cap, and I wrote, like, a research paper: This is why I shouldn't have an innings cap, this is why I should finish out the year,” Norris said at season’s end. “And so when I handed them that, I think maybe they reconsidered it.”

Said manager Ron Gardenhire: “He wrote a nice big message, and it was on a little bitty page, and it was really neatly written in little bitty words, and I can't hardly freaking see them. But it basically read: 'Don't shut me down.'”

Norris did not have to file a report, handwritten or typed, to describe his season when it was all done. But it was clear that the stretch run he pitched made a huge difference. As he heads toward 2020 preparing to compete for a rotation spot, he’s much better off for it.

“I think it's a step in the right direction,” Gardenhire said. “I think he feels good about himself.”

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Norris has a lot of reasons for that: In many ways, this was the best of his four full seasons as a Tiger. He finished second on the team in WAR according to baseball-reference, trailing only rotation mate Matthew Boyd. But he also has plenty he can improve upon if he’s going to use his 2019 campaign as a springboard to his long-awaited vault to full-time starter.

What went right?
For Norris, it always starts with health. He had been on the injured list every season since joining the Tigers in 2015, including core surgery that cost him four months in 2018. Norris' rigorous training program last winter paid off with his first full, healthy season, as he set career highs with 29 starts, 32 games and 144 1/3 innings. It was the Tigers’ caution over the injury risk, rather than any actual injury, that limited him down the stretch.

“My biggest thing this year was the night before and the day of my start,” Norris said. “Of course, you wake up and have different anxiety than the other days. This year, if I ever started feeling an ounce of doubt, I'd be like, 'You know what, I trained hard.' And as soon as I uttered those words in my head, that doubt and fear was gone, and I'd just walk to the field. I trained hard. I checked every single box. Whatever happens, happens. I have zero fear. Nobody can knock me on that. If I go out there and give up 15 runs, that doesn't matter because I worked my butt off every day. That was the biggest thing, because it alleviated a ton of stress for me.”'

By staying healthy all year, Norris found a long-sought routine as a starter. That made a big difference for him, which is why he argued he was better off making three-inning starts through season’s end rather than regular starts in August before packing it in for September. He slashed his walk rate from 3.9 per nine innings in 2017 and 2018 to a career-best 2.4. Even with a drop in his strikeout rate, his 3.29 strikeout-to-walk ratio was the best of his big league career.

Though Norris continues to look for his old fastball velocity -- he averaged 90.8 mph with the pitch this season, according to Statcast -- he made it work with improvement in his offspeed stuff. He allowed just a .212 average on his changeup, a pitch that had enough movement to induce a 37.6 percent whiff rate and 25.9 percent putaway percentage. His slider yielded a mere .211 average, .276 xwOBA and 29.8 percent whiff rate.

What went wrong?
Though Norris was limited to three-inning starts from mid-August on, he struggled to pitch deep into games before that as well, working into the seventh inning in just four starts all season. High pitch counts were an occasional issue, highlighted by the 80 pitches he threw over three innings against the Royals on Aug. 11 in the first of his abbreviated starts.

Though Norris has always been prone to hard contact on his fastball, the .613 slugging percentage and 92.1 average exit velocity off his heater in 2019 marked career highs. The pitch accounted for 17 of the 25 home runs he allowed, including a tape-measure drive from Juan Soto off the right-field upper deck at Comerica Park on June 28. His curveball, once a nice change-of-pace pitch for him, was not nearly as effective this year, yielding a .353 average and .412 slugging percentage.

Best moment
On July 31, the day the Tigers traded Nicholas Castellanos and Shane Greene just before game time, Norris tossed five scoreless innings with five strikeouts at Angel Stadium to help the Tigers to a 9-1 win over Los Angeles, earning Detroit its first series victory since May and its last series win of the season.

2020 outlook
Though Norris is eligible for arbitration for a second time, setting him up for a raise from his $1.275 million salary this year, the rebuilding Tigers want to stick with him and see what he can do with another offseason to get even stronger and work on his game. He won’t have a rotation spot guaranteed, but he could end up Detroit’s No. 2 starter if he shows enough in Spring Training to earn Gardenhire’s trust.

“I think he's going to go and fight for the rotation,” Gardenhire said. “Depending on how it all breaks down, he's a valuable asset either way, whether we use him as a starter or bring him out of the 'pen. He can chew up innings just like that coming out of the 'pen, too. He can pitch to righties and lefties. He's already proven that. Those guys are going to be very valuable no matter which way we go.”