Whenever contracts expire or are terminated by mutual consent -- usually at the end of a season or when the transfer window opens -- there is often a plethora of players that become available at no cost whatsoever that represents excellent value for teams eyeing a bargain.
Rarely do they come as decorated as Shinji Kagawa and, at the age of 31, presumably still with plenty left in those nimble and gifted legs.
It now appears that Kagawa that is headed to PAOK, which would be a major coup for the Greek outfit.
One of biggest names Asia has produced in the last decade, Kagawa rose to prominence as a key member of the Borussia Dortmund team that won back-to-back Bundesliga titles under Jurgen Klopp between 2010 and 2012.
A big transfer to Manchester United followed and, while that move has been identified as when the pivotal moment when his career began to decline, it has to be remembered that he still added a Premier League title to his medal cabinet the very next year.
A return to Dortmund initially proved the tonic he needed to regain his form, but he gradually faded from first-team action. The Japan international was loaned to Besiktas in 2019 prior to a permanent move to Real Zaragoza -- where his services were terminated halfway through the two-year contract he had signed.
It would seem a no-brainer for a club like PAOK to snap up his services. What were some of the other possibilities?
Remain in Europe at a lower level
Although he spent last season playing in Spain's second tier, Kagawa could still be a leading light in some of Europe's other leagues.
The Netherlands and Portugal would have been attractive destinations. A stint in Turkey would have been far from the worst option, especially following the example of compatriot Yuto Nagatomo, who joined Galatasaray after seven years at Inter Milan and ultimately earned a move to Ligue 1 with Marseille.
Return to a Big Five league but for a more modest club
Kagawa's title-winning experience in the Bundesliga and Premier League proved his talent was enough to compete at the highest level, so a return to one of the Big Five leagues wasn't completely out of the question.
The Japan international may have had to settle for a mid-table outfit rather than a title contender, and both West Ham and Everton were linked to him just two summers ago.
Rejoin his boyhood club
If Kagawa was to leave Europe, heading back to Japan would have been an option -- and where better to go to than where it all began?
Cerezo Osaka have a history of welcoming back former stars after campaigns abroad, with Hiroshi Kiyotake and Yoichiro Kakitani two perfect examples. Adding a player of Kagawa's ability would be a huge boost for the club as they look to seal a return to the AFC Champions League after a two-year absence.
Create a wave as one of Southeast Asia's biggest-ever imports
There was a rumour that Kagawa was being sized up by highly ambitious Singaporean outfit Lion City Sailors, although no move came to fruition. However, landing someone of his stature would certainly make for one of the biggest transfers ever in Southeast Asian football.
The main issue clubs face is pitching a vision that the 31-year-old could buy into, and few teams would even dream of securing his services. Still, it was not too long ago that Argentina legend Pablo Aimar made his way to Southeast Asia, joining one of those said exceptions in Johor Darul Ta'zim.
Become a marquee player in the MLS
Major League Soccer continues to be a glamorous destination for many of football's biggest names as they reach their twilight years, and one of Kagawa's old United teammates Javier Hernandez caused a stir when he signed for LA Galaxy.
Follow Honda's footsteps with a left-field move
From the time he left Japan to move to Dortmund at the age of 20, Kagawa has proven he is not afraid to move out of his comfort zone.
A less conventional route could have seen him follow in the footsteps of fellow countryman Keisuke Honda, who rose to prominence at AC Milan but boldly made Brazil his most recent port-of-call when he signed for Botafogo.