Celebrated his 41st birthday on the day of The 149th Open’s first round and ended the weekend with his best finish in five visits, a share of 15th.
He earned a return to the Championship for the first time since 2015 - the year after his best major finish of joint 12th in the U.S. Open - by winning the European Challenge Tour’s Le Vaudreuil Challenge.
Siem is a four-time winner on the DP World Tour, although there was an eight-year gap between his maiden title at the 2004 Alfred Dunhill Championship in South Africa and the 2012 French Open, where he beat Francesco Molinari by one.
In between partnered Bernhard Langer as Germany won the World Cup following a play-off with Scots Colin Montgomerie and Marc Warren, then added the 2013 Hassan Trophy and 2014 BMW Masters.
He reached a high of 48th in the world in 2013, represented his country in the 1998 and 2000 World Amateur Team Championship and also played for Europe against Asia in the 2012 Royal Trophy.