Amid 19 men emitting grunts which sounded like they were helping lift a refrigerator up eight flights of stairs, Walsh was the commander-in-chief. The world's latest Captain Cannonball said good riddance to the 7.26kg iron sphere with a venom previously not seen on the international stage.
He blitzed the field with consistency. The last five of his six throws went beyond 21.40m.
Walsh eclipsed the 21.26m which earned bronze at the same event two years ago in Poland. That 2014 throw placed him on a trajectory towards Rio Olympic gold and he is now a genuine contender to match Val Adams as a Games champion. His final effort was 16cm further than his outdoor PB.
Generally a relaxed character, Walsh switched into full competitive mode for this event. He replicated the build-up he will use at his maiden Olympics in August, but still found time before warm-ups to talk golf and the favourite courses he plays in his downtime with coach Dale Stevenson.
He was among the favourites to win gold in the absence of rivals Joe Kovacs, David Storl, O'Dayne Richards and Christian Cantwell -- the four men who threw further than Walsh outdoors last year. Regardless, he delivered when it counted and is now the thrower to chase in the countdown to Rio.
Four others in the field - Kurt Roberts, Michal Haratyk, Tim Nedow and Tomas Stanek - had thrown further indoors this year but Walsh's reputation for maintaining his composure in pressure situations shone through.
He paid tribute to Stevenson and New Zealand-based mentor Ian Baird for instilling the "virtue of patience" in his preparation, which saw him overcome a hip injury.
No New Zealand man has earned an Olympic shot put medal - Les Mills finished seventh at Tokyo in 1964 -- but Walsh looms as a pioneer.
He finished fourth at the world outdoor championships in 2015 but beat every major international competitor across the season. He also became the first New Zealand man to win a Diamond League meet, in Brussels, and set his 21.62m outdoor personal best in Zagreb.
Jacko Gill finished ninth, missing the top eight by 28cm after he threw 19.93m with his third attempt.
Elsewhere, Nick Willis reached the 1500m final with a comfortable time of 3m 41.53s in his heat. He needed only finish in the top six after the first heat was run slowly and his tactical awareness proved astute.
The final will be raced on Monday morning (NZ time).
