After some time Daria Ivanovna fled to St. Petersburg, leaving her daughter with Petr Vasiliev, a relative of hers, who raised Ekaterina under the surname of Petrova.

As a statistic encompassing all of the games of his career, Spassky's most-played openings with both the White and Black pieces were the Sicilian Defence and the Ruy Lopez.

[10] Spassky has beaten six undisputed World Champions at least twice (not necessarily while they were reigning): Vasily Smyslov, Mikhail Tal, Tigran Petrosian, Bobby Fischer, Anatoly Karpov, and Garry Kasparov.

Spassky made his international debut in 1953, aged 16, in Bucharest, Romania, finishing tied for fourth place with Laszlo Szabo on 12/19, an event won by his trainer, Alexander Tolush.

[12] In his first attempt at the Soviet Championship final, the 22nd in the series, held in Moscow 1955, Spassky tied for third place with 11½/19,[13] after Smyslov and Efim Geller, which was sufficient to qualify him for the Gothenburg Interzonal later that year.

Spassky's failure to qualify for the Portoroz Interzonal came after a last-round defeat at the hands of Tal, in a nervy game in the 1958 Soviet championship,[23] held at Riga.

A win would have qualified Spassky for the Interzonal, and a draw would have ensured a share of fourth place with Yuri Averbakh, with qualification possible via a playoff.

Spassky played on board one for the USSR at the 7th Student Olympiad in Leningrad,[29] where he won the silver,[30] but lost the gold to William Lombardy, also losing their individual encounter.

[39] In the 1964 Soviet Zonal at Moscow, a seven-player double round-robin event, Spassky won with 7/12, overcoming a start of one draw and two losses, to advance to the Amsterdam Interzonal the same year.

[40] At Amsterdam, he tied for first place, along with Mikhail Tal, Vasily Smyslov and Bent Larsen on 17/23, with all four, along with Borislav Ivkov and Lajos Portisch[41] thus qualifying for the newly created Candidates' Matches the next year.

Spassky was considered an all-rounder on the chess board, and his adaptable "universal style" was a distinct advantage in beating many top grandmasters.

[48] Spassky's first event after the title match was the fourth Chigorin Memorial, where he finished tied for fifth with Anatoly Lein as Korchnoi won.

[50] Spassky also won at Beverwijk 1967 with 11/15,[51] one-half point ahead of Anatoly Lutikov, and shared first place at Sochi 1967 on 10/15 with Krogius, Alexander Zaitsev, Leonid Shamkovich, and Vladimir Simagin.

In Spassky's first appearance after winning the crown, he placed first at San Juan, Puerto Rico in October 1969 with 11½/15, one and one-half points clear of second.

He won a quadrangular event at Leiden 1970 with 7/12, a point ahead of Jan Hein Donner, who was followed by Larsen and Botvinnik, the latter of whom was making his final appearance in serious play.

In November and December, Spassky finished the year by tying for sixth with Tal, scoring +4−2=11, at the Alekhine Memorial in Moscow, which was won by Stein and Anatoly Karpov,[64] the latter's first top-class success.

Before the match, Fischer had defeated Mark Taimanov, Bent Larsen, and Tigran Petrosian, but Spassky maintained his composure and competitiveness.

[72] Spassky finished in fourth place at the annual IBM tournament held in Amsterdam,[73] one point behind winners Petrosian and Albin Planinc.

[77] In Spassky's only tournament action of 1974, he played at Solingen, finishing with 8½/14 (+4−1=9), thus sharing third with Bojan Kurajica, behind joint winners Lubomir Kavalek and Polugaevsky, who scored 10.

[89] Spassky narrowly missed qualification from the 1982 Toluca Interzonal with 8/13, finishing half a point short, in third place behind Portisch and Eugenio Torre,[90] both of whom thus qualified.

He scored 8/15 to tie for sixth place with Alexander Beliavsky, behind joint winners Andrei Sokolov, Rafael Vaganian, and Artur Yusupov, and once again – one-half point short of potentially qualifying via a playoff.

In his return to tournament play after the loss to Korchnoi, he tied for first at Bugojno 1978 on 10/15 with Karpov,[98] with both players scoring +6-1=8 to finish a point ahead of Timman.

[114] However, Spassky's performances in the World Cup events of 1988 and 1989 showed that he could by this stage finish no higher than the middle of the pack against elite fields.

[119] In 1992, Bobby Fischer, after a twenty-year hiatus from chess, re-emerged to arrange a "Revenge Match of the 20th century" against Spassky in Montenegro and Belgrade; this was a rematch of the 1972 World Championship.

He said he had "the very brightest memories" of Mikhail Tal and told an anecdote from the 15th Chess Olympiad about Soviet analysis of an adjourned game between Fischer and Botvinnik.

[citation needed] Spassky succeeded with a wide variety of openings, including the King's Gambit, 1.e4 e5 2.f4, an aggressive and risky line rarely seen at the top level.

His third marriage, in 1975 in France, was to Marina Yurievna Shcherbachova, granddaughter of the Russian war general and a White movement activist Dmitry Shcherbachev.

I have often found that I have caught the basic idea of a position, the correct plan, but my great weakness is that I fail to follow the logical pattern through from beginning to end."

"[141] In 2005 Spassky signed the Letter of 5000 addressed to the Prosecutor General of Russia, along with Igor Shafarevich, Vyacheslav Klykov, Vasily Belov and other activists.

The petition suggested that all religious and national Jewish organizations that functioned on the territory of Russia according to the Shulchan Aruch codes should be shut down for extremism, warning about a "hidden campaign of genocide against the Russian people and their traditional society and values".