Donskoi started playing junior hockey at the age of five with the Finnish minor team Teräs-Kieko in his hometown of Raahe.[1] He moved to Oulu at the age of 15 and joined Oulun Kärpät's SM-sarja team for the 2007–08 season.
In April 2009, a 17-year-old Donskoi signed a three-year SM-Liiga contract with Kärpät.[2] He made his Liiga debut on 11 September 2009, away against Kiekko-Espoo. Donskoi scored his first Liiga goal in his third game on 19 September 2009, against Jokerit.[3] In November 2009, he injured his knee during practice and was out of action for a month.[4] In the season, Donskoi played 18 regular season games with two goals and two assists for four points. Donskoi played the rest of the season in the SM-sarja, where he won the championship in the spring of 2010.
Before the 2010 NHL Entry Draft, the NHL's scouting team rated Donskoi as the 14th most promising European forward. At the draft, the Florida Panthers would select him in the fourth round (99th overall).[5] Meanwhile, in the 2010 KHL Junior Draft, Avangard Omsk would draft Donskoi in the first round (13th overall).[6]
The 2011–12 season was more difficult for Donskoi than the previous one, as he would suffer from the so-called "curse of the second season."[9] Early in the season, Donskoi suffered from illness, so he would only manage ten points in the first 29 games.[10] In February 2012, he used the option in his contract and signed a one-year contract extension with the team.[11] Over the season, he would score a total of 25 points in 52 games. During the playoffs, Donskoi was one of the best from the Kärpät, as he would record three goals and three assists in six games.[10]
Donskoi's 2012–13 season was worse than expected. In October, he injured his wrist and was sidelined for a month.[12] Donskoi's playing level would remain low and his NHL contract also would expire during the season.[13] In December 2012, Donskoi would sign a contract extension with Kärpät until the spring of 2015.[14]
During the 2013–14 season, Donskoi did better than the previous season in terms of scoring. He would be Kärpät's third best scorer with 11 goals and 37 points. Especially during the fall, Donskoi would excel in the shootout.[15] In February 2014, Donskoi would sign a two-year contract extension with Kärpät.[16] Kärpät would go on to win the gold medal in the playoffs.[17]
For the 2014–15 season, Donskoi would set his single-season Liiga points record with 19 goals and 49 points, with which would make him Kärpät's best point collector and goal scorer. Donskoi shared fourth place in the entire Liiga's points standings with Tappara's Olli Palola. He led the playoff's plus-minus (+/-) standings with a rating of +15 and ranked second in the points standings with 22, ahead of line mate Joonas Kemppainen. Kärpät would win the Finnish championship again and Donskoi was awarded the Jari Kurri Trophy for the being the playoff's most valuable player (MVP). Donskoi was also selected for one of the Liiga's All-Star teams.[18]
In his first training camp and preseason with the Sharks, Donskoi impressed and made the club's opening night roster for the 2015–16 season. Donskoi scored his first NHL goal in his first NHL game, 7 October 2015, against goaltender Jonathan Quick of the Los Angeles Kings.[20] Donskoi surpassed expectations with the Sharks, cementing a regular roster position amongst the Sharks offense. In 76 games with San Jose, he compiled 11 goals and 25 assists for 36 points. Helping the Sharks reach the postseason, Donskoi appeared in every game, contributing with 12 points in 23 games as the club reached the Stanley Cup finals for the first time in franchise history. In Game 3 of the 2016 Stanley Cup Finals, Donskoi scored the game-winning goal in overtime,[21] but the team lost the series in six games to the Pittsburgh Penguins.
On 12 May 2017, the Sharks re-signed Donskoi to a two-year, $3.8 million contract.[22] He would record 28 goals and 31 assists over the next two seasons with the Sharks before becoming a free agent.
Colorado Avalanche (2019–2021)
As a free agent from the Sharks, Donskoi signed a four-year, $15.6 million contract with the Colorado Avalanche on 1 July 2019.[23] Acquired by the Avalanche to add scoring depth to the club's middle six forwards, Donskoi made his Avalanche debut on the opening night of the 2019–20 season, registering 2 goals in a 5-3 victory over the Calgary Flames on 3 October 2019.[24] Showing versatility, Donskoi played primarily alongside Nazem Kadri and Andre Burakovsky, and notched his first career hat-trick in a 9-4 blowout victory over the Nashville Predators on 7 November 2019.[25] He made his 300th NHL regular season appearance the following game against the Columbus Blue Jackets on 9 November.[26] He compiled a career high 14 points through the month of November, recording a career-high four points (2 goals, 2 assists), playing on the top-line in a 5-2 win against the Chicago Blackhawks on 30 November.[27] Donskoi recorded a career-high 16 goals and added 17 assists and 33 points in 65 games before the regular season was halted in March due to the COVID-19 pandemic. In the Avalanche's return to the playoffs, Donskoi added two goals in the round-robin stage and added 6 points in just 9 post-season games before missing the club's final 5 games to injury in a second-round defeat to the Dallas Stars.[28]
In his second season with Colorado, with added depth brought into the Avalanche line-up, Donskoi was primarily used in a third-line role alongside Tyson Jost and Valeri Nichushkin for the pandemic delayed 2020–21 season. Donskoi began the season with an offensive burst, compiling 28 points through 35 games, including collecting his second career hat-trick, notching the fastest 3 goals to start a game in franchise history (7:31) in a 9-3 victory over the Arizona Coyotes on 31 March 2021.[29] After missing 5 games through April in a COVID protocol related absence, Donskoi slowed in his production, finishing with a career high 17 goals while adding 31 points in 51 regular season games. In the opening round of the playoffs, Donskoi matched a career high of 3 points in a Game 2 victory over the St. Louis Blues on 19 May 2021.[30] He collected five points in 10 playoff games, unable to help Colorado advance past the second round for the third consecutive year.
Seattle Kraken and retirement (2021–2023)
On 21 July 2021, Donskoi's tenure with Colorado was cut short when he was selected from the Avalanche at the 2021 NHL Expansion Draft by the Seattle Kraken.[31] Donskoi struggled to find his offensive touch in the Kraken's inaugural season in 2021–22, posting only 2 goals and 20 assists for 22 points in 75 games.
In preparation for the 2022–23 season, Donskoi suffered a concussion after colliding during a pre-season game with Kole Lind during a game against the Vancouver Canucks.[32] After missing the entire season due to the concussion and its aftereffects, Donskoi announced his retirement on 27 August 2023.[33]
Donskoi played in the IIHF World Junior Championship in 2011 and 2012, In the former, he was Finland's third best scorer three goals and six points. In the latter tournament, Donskoi served as an alternate captain for the team.
Donskoi would play senior internationally representing Finland during the 2015 IIHF World Championship. He was the team's best point collector and third best scorer with 5 goals and 8 points.
Donskoi is one of six children; he has three brothers and two sisters. In his free time, he is interested in cars[35] and skateboarding. After the 2019 Stanley Cup playoffs, he returned to Finland and paid off the debt of a skating park his childhood friend owned.[36] He has Russian roots from his great-grandfather or grandfather.[37]