Following three years during which a persistent shoulder injury tormented him to the point that he considered suicide, the 26-year-old threw 70.01 metres to finish third and put himself within reach of a summons to Hampden.
The athlete would be a popular inclusion. Named as Scotland's team captain in Loughborough, Campbell received a swell of support ahead of what was only his second competition since 2011.
He acknowledged that he is still far short of the form which brought him UK titles but it was still heartening to see him restored to rude health.
"I could feel it coming," he said. "My run-up was just a mess during the last few rounds but I literally got just enough with the final throw. I'm just learning to do it again. It was a pressure situation and a few years ago, I might have lost my cool. But I'm pleased with the way I handled it."
Campbell must now achieve the qualifying mark once more before the June 8 deadline. Others warmed to the Leicestershire sunshine too and basked in a mission completed, with Emily Dudgeon effectively guaranteeing her place in the 800 metres in Glasgow with a run of 2:02.67.
That brought victory and the prospect of challenging Laura Muir, and potentially Lynsey Sharp, this summer. "It's going to be about performing at my best on the day," said the Cambridge medical student. "I won't worry too much about the other athletes on the team."
The scrap for supremacy in the women's hammer promises to fascinate right to the end. Rachel Hunter's decision to seek a hiatus from her nursing studies is reaping its rewards with the 20-year-old now trailing only Shirley Webb in the all-time Scottish list following a throw of 66.30m. That allowed her to finish as runner-up to Sophie Hitchon yesterday.
Susan McKelvie, who was already pre-selected for Glasgow, was fifth, Myra Perkins sixth and teenager Kimberley Reed seventh. With one to miss out, these are tense times for all concerned.
"It was a bit more than I was hoping for because I had an exam on Wednesday," said Hunter. "But conditions were good and my technique was on. I'm really chuffed."
Hunter credited the influence of Mark Dry or pushing her above and beyond in her recent performances. The Highlander was second in the men's event, with compatriot Andy Frost in third. Elsewhere heptathlon prodigy Morgan Lake won the high jump in 1.93m to break the UK junior record just six days after turning 17
The feat was matched by young Welshman David Omoregie, whose time of 13.23 seconds in the 110m hurdles leaves him fifth on the all-time world junior list.
n Great Britain's Gemma Steel came home second yesterday following a sprint finish at the Great Manchester Run. The 28-year-old improved on her fourth-place result at last year's event to finish Europe's most auspicious 10km race in 32 minutes and 10 seconds, as she just held off Kenya's Polline Wanjiku to the finish line.
The women's elite race was won by world and Olympic 10,000m champion Tirunesh Dibaba of Ethiopia, who finished over a minute ahead of Steel and Wanjiku in 31min 09secs.
In the men's event, victory went to another Ethiopian in 5000m and 10,000m world record holder Kenenisa Bekele, who crossed the line in 28:23. Bekele held off the challenge of Kenya's marathon world record holder Wilson Kipsang, who finished five seconds off the pace, while South African's Stephen Mokoko came home third.