The Open Variation (4. Ba4 Nf6 5. 0-0 Nxe4) is not quite as popular as the Closed Ruy Lopez, but it does have its adherents. Black typically does not intend to hold onto his extra pawn, but rather improve his position while While spends time regaining the lost material. There are numerous complex sub-variations available for both sides, some of which have been analyzed beyond the 20th move for each player.