Adams continued a winning streak that stretches back more than three years but it didn't come easily. She won the women's shot put with a throw of 20.15m but it was only narrowly further than China's Lijiao Gong, who threw 20.12m, and it took until the fifth round before she pulled out her only throw beyond 20m.
Gong was the only competitor to heave two attempts beyond the 20m mark. American Michelle Carter was third with a throw of 19.65m.
"This is definitely not what I wanted and I'm disappointed but, hey, you have to take the win," Adams said. "It was a bit of a fight but I felt really flat from the start to the end so to pull out a win and throw over 20m was OK. I have to be happy with that."
The competition at the Prefontaine Classic in Eugene, Oregon, started at 4.15am Swiss time where she had flown in from the previous day and she wondered if jetlag might have caught up with her. Adams is also a competitor who likes a bit of hype and the fact she came up against only four other competitors in a rapid-fire event might have been an issue.
But her struggles might buoy her opposition ahead of August's world championships given the 28-year-old two-time Olympic champion has dominated women's shot put for so long and a growing threat to her ascendancy is the burgeoning group of Chinese throwers.
"Gong threw really well today and had a season's best and had a couple of throws today over 20m," Adams said. "It was good to have competition for me and it was good to know I could still win even though I was feeling like s**t. I feel like I should be asleep right now.
"We fulfilled our first goal but I really wanted to throw a lot more. I'm in shape to throw a lot more."
Adams came in with a season's best of 20.37m to win her 12th national title but threw 20.75m at an exhibition event at The Cloud in March.
She said training had been going well but came into the event with a couple of niggling injuries and also sprained an ankle that threatened her participation - she said it's still black and blue.
Adams is gearing up for a tilt at a fourth world title in Moscow - hoping to become the first female thrower to win four world titles - and will also compete at Diamond League meetings in Lucerne, Paris, London, Stockholm and Zurich. Her next competition is in the Czech Republic in three weeks.
"My mental toughness and willpower and want to succeed is still there and that's why I was here [despite the injuries]," she said. I wanted to give it a chance. I was able to throw.
"I have to look at the bigger picture and the bigger picture is Moscow and we need to make sure we are fully prepared for that and ready to roll. Today was just a stepping stone towards that."
