Humber struck out nine and threw just 96 pitches in his first career complete game. The right-hander went to a three-ball count only three times.
It was quite a contrast to his first start of the season, when he went 5 1-3 innings and threw 115 pitches in a no-decision against Baltimore on Monday.
But Humber has become quite the reclamation project for Chicago, who picked him up on waivers from Oakland in January 2011. He was 9-9 with a 3.75 ERA in 163 innings last season, his first full season in the majors as a starter.
It was the third no-hitter thrown against Seattle. Mark Langston and Mike Witt of the Angels combined on one on April 11, 1990, and Dwight Gooden of the Yankees threw one on May 14, 1996.
Humber struck out the side in the second while cruising through the first four innings in just 45 pitches. Chone Figgins' fly ball to left in the fourth was the first ball to reach the outfield. Dustin Ackley followed with a hard liner to right that Alex Rios reached up and stabbed.
The White Sox moved farther and farther away from Humber as he approached history, leaving him alone as he sat on the bench in the Safeco Field visitors' dugout.
The nation grieved for those hurt, killed and affected by the Boston Marathon bombings. After one of the suspects was caught on Friday — following a day-long lockdown and manhunt — sports returned to Boston over the weekend.
Paul Konerko hit his second home run of the season and No. 398 for his career in the second. He also had a run-scoring single in the third.
Mariners starter Blake Beavan (1-2) allowed three runs and seven hits in six innings.
Humber becomes the latest one-time Mets pitcher who went on to throw a no-hitter elsewhere, a group that includes Nolan Ryan, Tom Seaver, Gooden and David Cone. New York has never had a no-hitter in its 51-year history. The only other team without one is San Diego, which began play in 1969.
NOTES: There were three no-hitters last year: Francisco Liriano of Minnesota, Justin Verlander of Detroit and Ervin Santana of the Los Angeles Angels. ... Seattle reliever Hisashi Iwakuma made his major league debut Friday night, becoming the last player on an Opening Day roster who was not hurt or optioned to the minor leagues to do so. . Rios came into Saturday with an eight-game hitting streak.
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