Landsteiner was a prolific junior curler, playing in the United States Junior Curling Championships six times, every year from 2007 through 2011. His best finish was in 2008 when he earned the bronze medal playing lead for Brad Caldwell. In 2011 Landsteiner participated at the World Junior Championships as alternate for Aaron Wald's team. Since ageing out of juniors in 2012 Landsteiner has played lead for John Shuster's team. With this team Landsteiner has played in seven US National Championships, only missing one year, 2018, because of obligations after the Olympics. Of the seven appearances at the National Championship, Team Shuster earned a medal six times, including gold in 2015, 2017, and 2019. Landsteiner's team placed first at the 2013 United States Olympic Curling Trials, then earned the final qualification spot for the 2014 Olympics at the qualification event when they won the second qualifier 8–5 over the Czech Republic. At the Winter Games the American men finished 9th out of 10 teams, with a record of 2–7. After the poor performance at the 2014 Winter Olympics, the United States Curling Association held an athlete combine to determine which curlers to include in their High Performance Program, aimed at having better success at the next Olympics. Landsteiner and Shuster were two of the athletes dropped from the HPP. In response, Shuster created a new team nicknamed "The Rejects" with Landsteiner at lead, fellow combine reject Matt Hamilton at second, and Tyler George at third, who hadn't attended the combine due to his work. They maintained this line-up for four seasons and found great success. At the National Championships in they defeated both HPP teams to win the gold medal. Representing the United States at the in Halifax, Nova Scotia, Team Shuster missed out on the playoffs when they lost a tiebreaker to Finland's Aku Kauste. As a result of its success, Team Shuster was added to the High Performance Program for 2016. Landsteiner and his team came up just short of defending their national title in, losing to Brady Clark in the final. Despite finishing in second, Team Shuster earned enough points throughout the season to secure their return trip to the. In Basel, Switzerland they defeated Japan's Yusuke Morozumi in the bronze medal match, earning the first World Men's medal for the United States since 2007. For the 2016–17 season they added Joe Polo, a former teammate of Shuster and George, as alternate and won the. At the, their third Worlds in a row, they lost in the bronze medal game against Team Switzerland, skipped by Peter de Cruz. At the 2017 United States Olympic Curling Trials Landsteiner and his team beat Heath McCormick's team in a best-of-three final series to represent the US at the Olympics a second time. In the 2018 Winter Olympics in PyeongChang, the US team lost four of its first six matches and needed to win all of its three remaining matches to qualify for the playoffs, but all of its remaining opponents were currently among the top four teams. Nevertheless, the US team won all three matches to finish the round-robin in third place with a record of 5–4. In the semifinals they defeated Canada's Kevin Koe, a two-time world champion, to reach the gold-medal match versus Niklas Edin's team representing Sweden. The gold-medal game was close through seven ends, with the score tied 5–5, but the United States scored five in the eighth end to set up a 10–7 victory. This was the first Olympic gold medal in curling for the United States. Landsteiner and Team Shuster again won the US National Championship in 2019. At the 2019 World Championship they finished 5th. They defended their United States title at the 2020 United States Men's Championship, defeating Rich Ruohonen in the final to finish the tournament undefeated. The national title would have earned Team Shuster a spot at the final Grand Slam of the season, the Champions Cup, as well as the chance to represent the United States at the 2020 World Men's Curling Championship, but both events were cancelled due to the COVID-19 pandemic. Their Champions Cup qualification will instead carry over to the 2021 Champions Cup.
Personal life
Landsteiner's hometown is Mapleton, Minnesota and he currently resides in Duluth, Minnesota. He graduated from University of Minnesota Duluth in 2013 with a degree in civil engineering. He currently works as a corrosion engineer for Lake Superior Consulting and is married.