You might think it unfair for such talented footballers as Xavi Hernández or Andrés Iniesta to have a second major skill. Yet they know enough about grass to have a future in horticulture once they hang their boots in the garden shed.
I mention this because in less than 24 hours the reigning champions (it's tempting to misspell that because the clouds were fat, heavy and grey again in Gniewino this morning) get their first sight, smell and feel of the pitch at the Arena Gdansk.
Some of the guys in red strips can talk to you about grass the way that a train spotter could make your day with a description of the differences between a Sprinter, a Blue Pullman and a Pendolino.
The reason that Poaceae (true grass) and Cyperaceae (sedges) occupy the thoughts of the European champions is that they passionately believe that the playing surface, for them, is just as important as the ball being properly inflated, the goals being the right size or the half-time cup of tea having the correct amount of sugar.
When Spain fly in matches it's because the ball is flying – you've seen their passing stats. What the Spanish (and most other good footballers at this tournament) want is that the surface is true, holds the studs well, and won't hamper their play.
However, what a key part of this squad also want is that the pitch is heavily watered before and during the match (half-time), and that the little green blades are shaved right down to something resembling stubble.
The more the grass is trimmed right down, they argue, the more their key passes which unlock defences can fizz along like an ice hockey puck hurtles between sticks at almost invisible speed.
Players like Xavi, Iniesta, David Silva and Xabi Alonso want their clever first-time passes to zip past an intercepting boot – something they think has separated them from the pack over the last two international tournaments.
So while today is all about training in Gniewino, most of Del Bosque's players – who will sit down this evening to watch the opening games – will be starting to ponder issues such as; 'How will our pitch be?' 'Will it be fast and thoroughly watered?' And 'Will it resemble the green, green grass of home?'
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