The Tynecastle head coach was in his second season in charge when Hearts, flying high following a title-winning campaign in the Championship, sold Osman Sow to Henan Jianye after the Chinese club offered over £1 million for a player in the final few months of his contract.
There’s a sense of deja vu in the current window with John Souttar attracting interest from Rangers and the English Championship and, if reports are to be believed, expected to sign a pre-contract with the Ibrox club imminently.
Though Hearts eventually stayed the course to finish third in 2015/16, performances dipped following the sale, including the ignominious Scottish Cup defeat to rivals Hibs.
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With more at stake this campaign, Neilson says it would take a “crazy bid” for Hearts to dispense with Souttar’s services before the end of this window.
He told the Scarves Around the Funnel podcast: “As we’ve said all along, our aim this season is to get European qualification.
“It’s brilliant for the club, brilliant for the fanbase and very lucrative to get into that position. If we finish third and either Celtic, Rangers or ourselves win the cup then we get into the play-off round for the Europa League. You win that, it takes you to a different level. Even if you don’t win that, you go into the Europa Conference League which, again, is another level. So it’s really important we keep the group together.
“You’ll remember five years ago when we lost Osman Sow. That had a real negative impact, not just in terms of losing the player but on the dressing room, and on the club and fanbase, that we’d lost one of our best players. Although we ended up that season finishing third, I felt we struggled to get our feet over the line.
“We have to keep our best players in the team. If that means it’s at the end of the season they go, then it’s the end of the season when they go.
“Unless there’s a crazy bid coming in, but I don’t expect there will be.”