Brad Keller continued his stellar start to the season, allowing three hits in 6 2/3 scoreless innings, as the Kansas City Royals defeated the Cincinnati Reds 4-0 on Wednesday in the first game of a doubleheader.

Keller didn't allow a hit until Tucker Barnhart led off the sixth with a bloop hit to center field. But Keller retired Joey Votto on a double play to squash the threat.

Keller (3-0) missed the start of the regular season as he built up strength after a positive COVID-19 test during summer training. But he certainly has hit the ground running. He pitched five scoreless innings against the Chicago Cubs in his first start, followed by six scoreless innings in Cincinnati in his last outing.

Keller struck out five and walked three -- Jesse Winker all three times. He gave up two singles in the seventh before giving way to Trevor Rosenthal. Rosenthal struck out Josh VanMeter to pick up his sixth save in as many chances.

Luis Castillo (0-3) took the loss for the Reds. He gave up four runs (three earned) on five hits in 3 1/3 innings. He walked two and struck out five.

The Royals jumped on Castillo in the first, but slowly. Whit Merrifield reached on an error by Votto. Hunter Dozier then walked with one out before Jorge Soler drove in Merrifield with a double to left. Ryan O'Hearn snapped an 0-for-10 with a flare to right field that scored Dozier and Soler.

Meanwhile Keller kept mowing down the Reds. With the exception of Winker, no Cincinnati player reached base in the first four innings. Winker came into the game hitting .586 (17-for-29) in his last 10 games.

The Royals got another run in the fourth when Merrifield singled through the drawn-in infield, scoring Adalberto Mondesi.

--Field Level Media