Diamondbacks manager Torey Lovullo said Iannetta's top lip was split. "So, we're taking every precaution possible to make sure he is OK".
Iannetta fell to the ground immediately and eventually walked off the field with towel over his nose.
The Diamondbacks had only thrown two no-hitters in their franchise's history, with Randy Johnson's ideal game for Arizona in 2004, and Edwin Jackson throwing a no-hitter in 2010.
Barbato said the pitch was unintentional, and Lovullo seemed to agree.
Glasnow (1-3) lasted just 2 2/3 innings, giving up seven runs, seven hits and two walks with three strikeouts.
The Diamondbacks' 11-4 win on Friday night was eclipsed by a frightening moment in the seventh inning, when Pittsburgh reliever Johnny Barbato lobbed a 93 m.p.h. fastball that hit Chris Iannetta square in the face.
"His slider's been very good with late action in the hitting zone", Lovullo said. "I found my pitch and hit it".
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On Afghanistan, Coats said the situation "will very likely continue to deteriorate, even if global support is sustained". But he said China can and should do more.
Iannetta hit a solo home run to start the third inning.
The Diamondbacks and Pirates have been beefing since 2014, when Pirates pitcher Ernesto Frieri hit Diamondbacks slugger Paul Goldschmidt in the hand, ending his season in August.
Twins 7, White Sox 6: Eduardo Escobar hit a three-run homer then added a fourth RBI with a double as visiting Minnesota beat Chicago. The next day, Pirates star Andrew McCutchen was drilled in the back with a fastball. The Giants, who have an MLB-worst 12-24 record, lost for the sixth time in seven games and for the 10th time in their last 12. A 93 miles per hour fastball would end up in Iannetta's face.
The Pirates are 53-25 in their last 78 Friday games, and 2-5 in their last seven road games versus a left-handed starter.
Drury also doubled and singled to improve his batting average at home to.448 (30 of 67), best in the majors.
Patrick Corbin (3-4) went six innings and gave up four runs, two on Josh Bell's homer.
Seattle used two singles and a wild pitch to put runners at second and third with one out in the seventh, but couldn't break the deadlock. Arizona was in total control by the time the hot-hitting Drury belted a towering shot into the left field seats for a 7-1 lead.
The Pirates made a pair of roster moves with the return of third baseman David Freese and utility player Adam Frazier from the disabled list.
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