Mainly due to the number of absentees, he appeared in goal for Round 12 of the Ukrainian Premier League on 1 November; He kept a clean sheet in a 3–0 win.

He made his debut for Dynamo in a UEFA Champions League play-off game against AFC Ajax, and with an impressive performance[3] subsequently established himself as the first-choice goalkeeper with his new club in the absence of the injured Oleksandr Shovkovskyi, at the age of only 17.

In November 2010, Koval was named by Spanish football magazine, Don Balón as one of the 100 best young players in the world alongside David de Gea, who had recently moved to Manchester United.

The game started well with Dynamo taking the lead, only for Koval to rush from his line as the opposing player made a dash forward, and foul him just outside the box with a poor tackle.

[6] On 3 March 2015, after participating in Dynamo's winter training camp, it was announced that Koval will return to Hoverla until the end of the season.

[10] At the end of the loan period, Al Fateh was able to buy Koval's transfer from Dynamo Kyiv and signed the goalkeeper to a three-year deal.

[14] On 13 January 2024, Aris Thessaloniki announced the signing of Koval to a 2.5-year contract, whilst also loaning him out to Kalamata until the end of the current season.

[16] Koval was called up to the senior national team in June 2011 for matches against Uzbekistan and France, but did not play in any of these games.