THE problem with shooting up the leagues is that some players continue the journey on their own: they leave.

Inverness Caledonian Thistle's rise from finishing 10th in the Clydesdale Bank Premier League last season to a probable place in the top three this time was never going to go unnoticed. Climbing the division attracts scouts as well as praise and the cherry-picking of Inverness has begun.

Andrew Shinnie – who five months ago became the Highland club's first Scotland internationalist and is on the shortlist for Cheque Centre PFA Scotland's player of the year award – has signed a pre-contract agreement to join Birmingham City. Goalkeeper Antonio Reguero will join Kilmarnock. Terry Butcher has shown his managerial skills by tying up most of his squad on contracts but Aaron Doran, the talented winger, has still to commit.

It is testimony to the pulling power of Inverness, and Butcher's persuasiveness, that Shinnie thought long and hard about signing a new contract to stay for a third season. Instead he found Birmingham and the npower Championship irresistible. "It was a difficult decision and I thought about staying another year, but this is a great opportunity for me," said the forward. "I just thought at my age, I will be 24 in the summer, a three-year deal in a good league like the Championship was the right decision."

Shinnie – who will leave his brother Graeme behind when he leaves Inverness – began his career at Rangers, making his debut in 2007 but failing to break through properly and being sent out on loan to Dundee twice. He was allowed to leave Ibrox and moved to Inverness in the summer of 2011 but this has been his breakthrough season.

He has scored 15 times in 41 appearances, made his Scotland debut against Luxembourg in November, is shortlisted for player of the year and, to Inverness's dismay, he will play only four more times for them before moving to the Midlands.

"I have always wanted to test myself down south and I have a good opportunity to do that next year," he said. "Birmingham have always shown a big interest in me and watched me 15 times this season. I think they wanted to do something in January but, while that didn't go through, they made it known they still wanted me. They are a big club with brilliant training facilities, a good stadium and a great manager so they sold it pretty well to me.

"Obviously you have the play-off system so the top six teams in the league have a chance to go up. If we could get promotion that would be unbelievable but first and foremost I just want to do my best. Another good reason for moving is it might help me with Scotland. A lot of Scotland players at the moment are based in English leagues. It can be harder to get in it from the SPL and hopefully if I go down there and do well I will get a few more call-ups."

Butcher did what he could to keep him. "He was hoping I would stay and I dragged it out a bit but I wasn't totally convinced I wanted to move on," said Shinnie. "I did think about giving another year back to the club, but I have had a great season and apart from reaching a cup final I don't see what more a club like Inverness could have done. I just felt it was a good time to try a new challenge in my career and I think the manager is happy for me. He understands life decisions and he wasn't going to stand in my way."

The move looks good for Shinnie, but what about Inverness? "I think they can definitely maintain this form next season. The gaffer has done well getting a lot of the squad signed up for next season," added Shinnie. "There is a lot for them to build on and if they can add a few then hopefully they will be fine.

"We lost Johnny Hayes and Gregory Tade last summer and they were our main scorers. That was a blow but in pre-season I could see signs of a good team. We took a little while to gel and although we were not playing badly people were starting to doubt the gaffer. People were saying he was under pressure. But the only thing more he could have done this season was reach a cup final. It would be amazing if I could sign off with Inverness in Europe."