Kyle Harrison showed why he is the No. 1 left-handed pitching prospect in baseball Tuesday night.

The 21-year-old left-hander absolutely shoved for Triple-A Sacramento in the team's eventual 7-4 loss to Oklahoma City. Harrison notched a season-high nine strikeouts over four innings of hitless baseball in a downright dominant outing.

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The No. 15 overall prospect had his fastball working to perfection. Harrison recorded nine punchouts, seven of which came by way of the heater.

The 2020 third-round pick started off by punching out two of the three first batters with the gas, and from there, he never took his foot off the pedal. Harrison struck out three more in the second inning, followed with two more whiffs apiece in the third and fourth.

The only baserunners for the Dodgers during his start came after a fielding error by second baseman Isan Diaz in the second, a walk in the third and a plunked batter in the fourth.

The top Giants prospect came out after throwing just 61 pitches, 40 of them for strikes. After the stellar start, Harrison sports a 4.11 ERA with a string of promising performances and 56 whiffs in just 30 2/3 innings at the Triple-A level. Through 10 starts, opponents have hit just .197 off the 21-year-old for a 1.47 WHIP. 

On May 6 against Las Vegas, Harrison put together a similar start in which he fanned seven through four innings of one-hit ball. In that start, 31 of his 50 pitches were his 65-grade fastball, the same pitch that was working for him Tuesday.

Harrison continues to show he has lights-out stuff this season, now it's all about finding consistency ahead of his eventual MLB debut. In his two previous outings for the River Cats, the California native was tagged for a combined seven runs on six hits over seven frames. Even then, though, Harrison still struck out a total of 13 batters.