The Mets learned firsthand this year that nothing is certain in baseball, not even their potent young arms. So for last night’s MLB Draft — the same night Jacob deGrom threw a complete game — they shored up the one part of their organization that once seemed overflowing with abundance.

With the 20th pick in the amateur draft, the Mets chose Oregon pitcher David Peterson, a potent lefthander who struck out 282 batters in his three years in Division I baseball. He has one more year of eligibility, but is likely to accept the hefty signing bonus that comes with the pick.

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The 6-6, 240-pound Peterson is the first All-American in Oregon baseball history, and was 11-4 with a 2.51 ERA this year. Peterson struck out a school-record 140 batters this season over 100 1⁄3 innings, while allowing only 15 walks. He was originally picked in the 28th round of the 2014 draft by the Red Sox before opting to pursue his college career.

According to Scout.com, he sports a mid-90s fastball with good movement, and a plus sinker. He struck out 20 batters in an April 28 win over Arizona State and also had a 17-strikeout game on March 3, against Mississippi State.

In the second round, the Mets took third baseman Mark Vientos of American Heritage School in Plantation, Florida, with the 59th overall pick.