Aaron Nola finishes off his season in 3-1 loss

Aaron Nola reached into his glove Monday night, adjusted his grip in the fifth inning of a 3-1 loss to Washington, and delivered his final strikeout of the season. He used his curveball – the pitch that continued to blossom this season – for strike three. It was excellent as ever.

Monday was Nola's final start of 2017, a season in which he seemed to emerge as the pitcher the Phillies believed he could be when they drafted him three years ago. Nola threw the curveball for eight of his nine strikeouts and allowed two runs in six innings.

The Phillies equipped a six-man rotation last week, meaning Nola will not start Sunday's season finale. The righthander walked off the mound with some real hope for what he can become in 2018. And that was hard to imagine five months ago when he had a shaky start to the season and landed on the disabled list.

But he ended his third season with a 3.00 ERA in his last 18 starts. His 184 strikeouts are the most in franchise history for a pitcher who has made less than 30 starts. And half of those strikeouts came via the curveball. Nola had a solid curveball when the Phillies drafted him, but it seemed to reach another level this season.

The Phillies know little about their rotation except that Nola will be a part of it. The rest of the four openings remain open. The Phillies will likely sign a veteran arm or two this winter and fill the remaining slots with some of the young pitchers that joined Nola this season.

The Phillies used six starters this season aged 25 or younger. It is the curveball that sets Nola apart. He is the lone young arm with a secondary offering that seems to consistently yield results. Opponents entered Monday batting just .182 this season against his curveball. The pitch's success makes the precise command of Nola's fastball that much more effective.

"The fastball is good enough that people have to respect it and then the curveball is obviously lights out," catcher Andrew Knapp said. "He can throw it in any count and when you can do that you can really switch counts."

"He's locating his pitches. When you locate those pitches, you don't hang them. You put them where you want to. That's what makes him look better," manager Pete Mackanin said. "All his pitches were much better. Early on in that first and second inning he wasn't really locating well. He was missing spots, quite a few. Then he settled down and was what we always have known he can do."

Nola paired his fastball and curveball this season with a changeup, which he began to work tirelessly on during spring training and fine-tuned throughout the year. It is a solid pitch to use against lefthanded batters and is a needed third offering. Nola said the development of the pitch is what he is most pleased about from 2017.

"It's been the cherry on top being able to throw that right on right. It's a hard pitch to hit when you're a lefthanded hitter, but when you're righthanded coming to that back foot it's a really good pitch," Knapp said. "He was kind of getting on the side of it today, but towards the sixth inning it was good."

The Nationals scored their lone runs off  Nola with a two-run homer in the second. Michael A. Taylor connected on a fastball and sent it into the left-center stands. Nola allowed just two more batters to reach second base. He cruised and the homer was his only mistake.

Odubel Herrera, who had two hits, homered in the fourth with a rocket to right field. That was all the Phillies could muster. Rhys Hoskins, who has not homered since Sept. 14, flew out to the warning track and went 0 for 4. Knapp had a hit and walked twice. Nick Williams struck out three times.

The final strikeout of Nola's season – No. 184 – came against Ryan Zimmerman. The veteran hitter took a looping swing at the looping pitch and came up empty. He tossed his bat in the air, flipping it end over end before it hit the dirt. Another hitter was left befuddled by the curveball. Nola's season would end an inning later and there is already anticipation for next year.

"Better than last year," Nola said about 2017. "Stayed healthy all year besides my back issue that I had early in the year. I felt like I stayed within myself and within my routine all year, pretty well. Going into next year, can kind of just build on the things that need to be worked on."