Arrieta is the first pitcher to win at least 22 games in a season since Justin Verlander won 24 in 2011, and the first in the NL since Brandon Webb won 22 in '08.
"He's unbelievable," Cubs first baseman Anthony Rizzo said of Arrieta, who finished the season 22-6. "You get guys on base all the time and they say they've never seen anything like it. It's a credit to him. He works hard, and deserves everything he gets and is about to get. Now we've got the biggest games of our lives coming up. We'll be ready."
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This was Arrieta's 20th quality start, and he's 16-1 with an 0.86 ERA in that stretch. His only loss was July 25 when the Phillies' Cole Hamels no-hit the Cubs at Wrigley Field.
For the season, Arrieta posted a 1.77 ERA, and he's the first Cubs qualifying pitcher to finish with a sub-2.00 ERA since Grover Cleveland Alexander recorded a 1.91 ERA in 1920. He's the first pitcher since Dwight Gooden in 1985 to win 22 games and post an ERA under 2.00.
And if those numbers aren't staggering enough, since the All-Star break, he's given up nine earned runs over 107 1/3 innings for an 0.75 ERA, the lowest ERA after the break in Major League history. He's 12-1 in those 15 starts.
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Cubs manager Joe Maddon knows good pitching. He had David Price in his Rays rotation when the left-hander won the American League Cy Young Award in 2012. Is Arrieta's year the single best season the manager has seen?
"Absolutely," Maddon said. "David won the Cy Young and was outstanding. But I've not seen [what Arrieta's done]; I don't think a lot of people have. If you break [Arrieta] down from the All-Star break to the end, I guess Mr. [Bob] Gibson is the only other dude, and he was my favorite pitcher growing up. You're hard pressed to find a better performance than [Arrieta] has put on for the last several months."
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Well, Arrieta actually has had a better second half than the Cardinals' Hall of Famer, who was 11-4 with a 1.19 ERA in 16 starts after the break in 1968.
"That's like sacred ground for me," Maddon said when told his ace was better. "If he's beating Bob Gibson, that's pretty impressive."
Will Arrieta beat the Dodgers' tandem of Zack Greinke and Clayton Kershaw and win the NL Cy Young Award?
"If that did not clinch his award, I don't know what would," Maddon said of Arrieta's outing.
Arrieta isn't thinking about awards. He's got at least one more start.
"Wednesday is the most important thing for us right now, and getting ready for that day is pretty much the most important thing to everybody here," he said.
And how would Rizzo approach Arrieta?
"See the ball and hit the ball," Rizzo said. "You've got to pick a side of the plate and try to stick with it. He makes mistakes like everyone else. It's a good thing I don't have to face him."
Early this season, Maddon said Arrieta had another level. The right-hander appears to have found it.
"The repetition of delivery is there, the stuff is the same as it was two months ago," Maddon said. " It's incredible. For all those reasons, I think he can continue this. ... To have the honor of managing that is pretty incredible."