I'm not sure this entirely applies here, but there is a lesser discussed grammar rule concerning whether to use the singular or plural when talking about groups of people. Whenever you're referring to singular objects which represent groups of people (people being a plural concept), the decision to make the verb singular or plural depends on the context of the sentence, and whether or not the members of the group are acting as one or as individuals.
My favorite set of examples is the following:
Congress were arguing about whether or not to pass the bill.
vs.
Congress agrees that the bill should be passed.
When the situation denotes that the group's members are acting in varying ways (they could be disagreeing, like in the first example), a plural verb is appropriate. Yet when the group's members are acting similarly, you can safely use the singular since these individual actors are behaving as though a singular object.
So yeah, I mean in your example Leicester's players are still technically acting "similarly" in that they're all outsiders, but I suppose the report used the plural to emphasize the fact that a football club is a pretty substantial organization of individuals.