Italy's joint Olympic champion Gianmarco Tamberi avoided a shock early exit by scraping into the men's high jump after qualification at the World Athletics Championships on Friday.
There was no such drama on the track as American veteran Allyson Felix's hopes of a medalling swansong were kept alive as the US team went through to the final of the 4x400m mixed relay.
Felix, 36, didn't race the morning round. Instead a quartet made up of Elija Godwin, Kennedy Simon, Vernon Norwood and Wadeline Jonathas clocked a word lead of 3min 11.75sec to advance to the final (0250 GMT) where one of the women will cede their place to Felix.
Also qualifying for the final are the Netherlands, the Dominican Republic, Poland, Ireland, Italy, Jamaica and Nigeria, but all eyes will be on whether 11-time Olympic medallist Felix can sign off her career with a 19th world medal.
Tamberi was involved in one of the signature moments of last year's Tokyo Olympics when he shared gold with friend and rival Mutaz Essa Barshim of Qatar.
But Tamberi made hard work of qualifying in the searing sun at Hayward Field in Eugene, Oregon, in the first day of action of the championships which run until July 24.
The Italian needed three attempts at both 2.25 and 2.28m, each time dramatically slumping to the mat in sheer relief after finally clearing the bar.
Barshim had no such troubles, smoothly progressing to Monday's final in his bid to nail a third consecutive world title.
"I'm counting on all my experience," said Barshim, who has competed very little this season.