Leaving gaps definitely and I think there is a naivety in the way a few players challenge for the ball. And we do need to press higher, but not doing that is often a sign of nerves.I don't think it's individuals. it's either a deliberate tactic or it's a general fear of overcommitting an attempted tackle and leaving a gap.
How many times have we heard Martinez, in post match interviews, mention our lack of intensity ? Maybe they just stand out in my mind, but it seems to be fairly common ?
But suppose I just feel like it's more than fair for fans to get frustrated with tactics or players who don't look bothered. But when you consider that Kone or Lennon would have fans on their back a lot sooner than Mirallas then desire to work for the team clearly won't win a lot of fans round.
Although I'm just waffling a bit now, the general point is that there's a massive gap between passionate discussions on players and tactics and people singling out players and clearly causing nerves and mistakes. Of course not every mistake is down to nerves but I just don't see how any fans can think it helps