Ruy Lopez strengthened when Simen Agdestein and some other Norwegian players adopted the variation. In 1995 Jonathan Tisdall published the article "Ruy Lopez. The Norwegian Variation" in New in Chess Yearbook 37. The Graz Defence, Classical Defence Deferred, and Møller Defence combine 3...a6 with the active move ...Bc5. For a century it was believed that it was safer for Black to place the bishop on e7, but it is much more active on c5. White can gain time after playing d4 as the black bishop will have to move, but this does not always seem to be as important as was once
Ruy Lopez careful play White is held to gain an advantage. The best moves are 4.Nxd4 exd4 5.O-O Bc5 6.d3 c6 7.Ba4 Ne7. This defence was published in 1843 in Paul Rudolf von Bilguer's "Handbuch des Schachspiels" and explored by Henry Bird in the late 19th century. Bird played it as Black at least 25 times, scoring +9 =3 −13 (nine wins, three draws, thirteen losses). Bird's Defence was later used a few times in tournament play by Siegbert Tarrasch, Boris Spassky, and Alexander Khalifman. Although it is still sometimes seen as a surprise weapon, no strong master since Bird has adopted