Petrópolis was one of two Interzonals feeding the next Candidates cycle, and it belonged to the home crowd. The 21-year-old Brazilian Henrique Mecking went through the eighteen-player field unbeaten to win outright, a milestone for Brazilian chess. A three-way tie for second then had to be settled in a separate playoff in Portorož.
Two Interzonals, one road to the Candidates
For the 1973 cycle FIDE split the Interzonal stage across two tournaments — one in Leningrad, the other in the Brazilian mountain resort of Petrópolis — with the leading finishers of each advancing to the Candidates matches. Eighteen players contested the Petrópolis round-robin, thirteen of them grandmasters, among them Efim Geller, Lev Polugaevsky, Lajos Portisch, former world champion Vasily Smyslov, David Bronstein and Paul Keres.
For the young host nation the tournament was an occasion in itself: Brazil had never staged an event of this weight, and its own leading player was in the field with a real chance of qualifying.
Mecking wins unbeaten
Henrique Mecking, then twenty-one, met the pressure of playing at home by not losing a single game. He finished on 12/17 — seven wins and ten draws — a full half-point clear of the chasing pack, and took first place outright. It made him the first Brazilian to win an Interzonal and carried him directly into the 1974 Candidates.
Behind him the tournament was desperately close: Geller, Polugaevsky and Portisch all tied on 11½/17, sharing second through fourth and leaving the two remaining qualifying places to be settled away from the board.
The Portorož play-off
Because three players were level for the last two Candidates spots, a play-off was held in Portorož, Yugoslavia. Portisch won it with 5½, Polugaevsky scored 3½, and Geller finished on 3 — so Portisch and Polugaevsky joined Mecking in qualifying, while Geller was eliminated.
Those play-off games were contested by only the three tied players, and they explain why the summed-points cross-table can appear to place Portisch, Polugaevsky and Geller above Mecking: the archive folds the Portorož play-off in with the Interzonal proper. On the round-robin that actually decided the tournament, Mecking finished first.
Final standings
| # | Player | Score | Record | Games |
|---|---|---|---|---|
| 1 | Mecking, Henrique | 12/17 | +7 -0 =10 | games |
| =2 | Portisch, Lajos | 11½/17 | +7 -1 =9 | games |
| =2 | Polugaevsky, Lev | 11½/17 | +7 -1 =9 | games |
| =2 | Geller, Efim P | 11½/17 | +7 -1 =9 | games |
| 5 | Smyslov, Vasily V | 11/17 | +7 -2 =8 | games |
| 6 | Bronstein, David Ionovich | 10½/17 | +7 -3 =7 | games |
| 7 | Hort, Vlastimil | 10/17 | +6 -3 =8 | games |
| 8 | Savon, Vladimir A | 9½/17 | +5 -3 =9 | games |
| =9 | Ivkov, Borislav | 9/17 | +2 -1 =14 | games |
| =9 | Ljubojevic, Ljubomir | 9/17 | +6 -5 =6 | games |
| 11 | Reshevsky, Samuel Herman | 8½/17 | +5 -5 =7 | games |
| =12 | Panno, Oscar | 8/17 | +3 -4 =10 | games |
| =12 | Keres, Paul | 8/17 | +3 -4 =10 | games |
| 14 | Gheorghiu, Florin | 7½/17 | +3 -5 =9 | games |
| 15 | Biyiasas, Peter | 6½/17 | +3 -7 =7 | games |
| =16 | Tan, Lian Ann | 3/17 | +0 -11 =6 | games |
| =16 | Hug, Werner | 3/17 | +0 -11 =6 | games |
| =16 | Kagan, Shimon | 3/17 | +2 -13 =2 | games |
Cross Table
| Rank | Player | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | Mecking, Henrique | ½ | ½ | ½ | 1 | ½ | ½ | 1 | ½ | ½ | 1 | ½ | ½ | 1 | ½ | 1 | 1 | 1 | |
| 2 | Portisch, Lajos | ½ | 0 | ½ | ½ | ½ | ½ | ½ | 1 | ½ | 1 | ½ | 1 | ½ | 1 | 1 | 1 | 1 | |
| 3 | Polugaevsky, Lev | ½ | 1 | ½ | ½ | ½ | ½ | ½ | ½ | ½ | ½ | 0 | 1 | 1 | 1 | 1 | 1 | 1 | |
| 4 | Geller, Efim P | ½ | ½ | ½ | ½ | 1 | ½ | ½ | ½ | 1 | ½ | ½ | 1 | 1 | 0 | 1 | 1 | 1 | |
| 5 | Smyslov, Vasily V | 0 | ½ | ½ | ½ | 0 | 1 | ½ | ½ | 1 | ½ | ½ | 1 | 1 | ½ | 1 | 1 | 1 | |
| 6 | Bronstein, David Ionovich | ½ | ½ | ½ | 0 | 1 | 0 | ½ | ½ | 1 | 1 | 1 | ½ | 1 | ½ | 1 | 1 | 0 | |
| 7 | Hort, Vlastimil | ½ | ½ | ½ | ½ | 0 | 1 | 1 | 0 | 0 | 1 | ½ | ½ | ½ | 1 | ½ | 1 | 1 | |
| 8 | Savon, Vladimir A | 0 | ½ | ½ | ½ | ½ | ½ | 0 | ½ | 0 | 1 | 1 | ½ | ½ | 1 | 1 | ½ | 1 | |
| 9 | Ivkov, Borislav | ½ | 0 | ½ | ½ | ½ | ½ | 1 | ½ | ½ | ½ | ½ | ½ | ½ | ½ | 1 | ½ | ½ | |
| 10 | Ljubojevic, Ljubomir | ½ | ½ | ½ | 0 | 0 | 0 | 1 | 1 | ½ | 0 | 1 | ½ | 0 | 1 | ½ | 1 | 1 | |
| 11 | Reshevsky, Samuel Herman | 0 | 0 | ½ | ½ | ½ | 0 | 0 | 0 | ½ | 1 | 1 | ½ | ½ | 1 | 1 | ½ | 1 | |
| 12 | Panno, Oscar | ½ | ½ | 1 | ½ | ½ | 0 | ½ | 0 | ½ | 0 | 0 | ½ | ½ | ½ | ½ | 1 | 1 | |
| 13 | Keres, Paul | ½ | 0 | 0 | 0 | 0 | ½ | ½ | ½ | ½ | ½ | ½ | ½ | ½ | ½ | 1 | 1 | 1 | |
| 14 | Gheorghiu, Florin | 0 | ½ | 0 | 0 | 0 | 0 | ½ | ½ | ½ | 1 | ½ | ½ | ½ | 1 | ½ | ½ | 1 | |
| 15 | Biyiasas, Peter | ½ | 0 | 0 | 1 | ½ | ½ | 0 | 0 | ½ | 0 | 0 | ½ | ½ | 0 | ½ | 1 | 1 | |
| 16 | Tan, Lian Ann | 0 | 0 | 0 | 0 | 0 | 0 | ½ | 0 | 0 | ½ | 0 | ½ | 0 | ½ | ½ | ½ | 0 | |
| 17 | Hug, Werner | 0 | 0 | 0 | 0 | 0 | 0 | 0 | ½ | ½ | 0 | ½ | 0 | 0 | ½ | 0 | ½ | ½ | |
| 18 | Kagan, Shimon | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | ½ | 0 | 0 | 0 | 0 | 0 | 0 | 1 | ½ |
Each cell shows the row player's recorded results against the column player. ● = same player.