Double reigning 60m champion Richard Kilty will compete for Great Britain in the European Indoor Championships in Glasgow after originally missing out on a place in the squad.
The 29-year-old was left "struggling mentally" after his time of 6.63 was not enough to meet British Athletics' qualifying time of 6.60 seconds.
The European Athletics Council (EAC) has now invited Kilty to compete in what is described as a "special case".
Kilty says he will aim for a hat-trick.
"Our invitation is really a special case," EAC president Svein Arne Hansen said.
European Athletics permits anyone who has run 6.78 seconds to compete at the tournament, but British Athletics implemented their stricter selection requirement of 6.60 seconds - meaning only Reece Prescod and Chijindu Ujah were eligible, but both men declined.
The governing body was then only able to take 100m times from last summer into consideration, meaning Ojie Edoburun - who finished last in the 60m at last week's British Championships - was Britain's only option, with Kilty initially being told he did not have a place.
Reacting to the U-turn, Kilty said: "I am really thankful to European Athletics for giving me the opportunity to stand on the start line and realise the dream I set after I had my Achilles surgery."
"The main thing for me has been to get on that start line as a defending champion at a home championships."
He said he now "feels phenomenal" after "struggling mentally for a couple of days" after the original team announcement.
I struggled mentally for a couple of days after the team announcement but now I feel phenomenal.
Richard KiltyDouble reigning 60m champion
"I can put it to the back of my mind and run for my family, my fans and the home crowd - that is all I am thinking about," he said, adding he "can't wait to stand on the start line and try to make history" by winning a third consecutive title.
Kilty now has the chance to defend the European indoor 60m title he won in Prague in 2015 - a year after becoming world champion over the distance in Sopot - and then retained in Belgrade two years later.
Richard Kilty welcomes the news on Twitter
Hansen said: "This situation of a defending champion from the host nation being fit but not making his or her national team is fairly unusual.
"It helps the individual athlete, of course, but more importantly it shows that we are ready to react to opportunities that will help our events succeed."
Noting that champions at the outdoor championships automatically qualify for the following edition, Hansen added: "We all know that it adds interest for the public when they see that national stars, especially champions, will be competing.
"I am looking to the future and although there are factors we need to discuss, I intend to ask the council to consider extending the automatic qualification rule to the indoor championships."
The size of Great Britain's team is now 49, an outright record for an European Indoor Championships.
The European Athletic Indoor Championships take place in Glasgow from 1 to 3 March.