By Daniel Moxon Sergio Perez admitted it would be “a blow” if team-mate Max Verstappen left Red Bull. Just two weeks ago, the Dutchman threatened to walk away if ally Helmut Marko was forced out of the team. Marko has been going up against team principal Christian Horner in an internal power struggle which has overshadowed a successful start to the new season. Mirror Sport understands that, if it comes to it, Red Bull would prefer to keep Horner and would allow Verstappen to leave if forced to pick between them. But the ideal outcome remains that all their key personnel remain on board. And Pe…