Game 19 of the world chess championship reached adjournment yesterday in Seville with a smell of blood in the air.

Nobody at the Teatro Lope de Vega, where the match is being played, could say for sure whether challenger Anatoly Karpov had a winning position. But he certainly had an advantage over defending champion Gary Kasparov in the rook and pawn endgame. His passed pawn on a6 was well guarded and only two squares away from becoming a queen. If he could trade off a pair of rooks, he could have a won game.

In any case, after adjournment Karpov had 19 hours, with a team of experts working around the clock, to look for a winning line of play. But even without such concentrated analysis, it is clear that Karpov is struggling for a win, Kasparov for a draw, and each seems to have about a 50-50 chance of getting what he wants.

The match stands tied at 9 to 9, with each player having won three games and drawn 12.

For the last dozen moves before adjournment yesterday, both Karpov and Kasparov seemed to be marking time so that they could sit down with their teams and take a long, cool look at the situation. Kasparov, hanging on for dear life, had as much reason as Karpov to avoid committing himself before adjournment. But the curious minuet of rooks and kings, leading up to Move 40 and the end of the day's work, seemed to be mostly Karpov's idea. While killing time with repetitious moves, he carefully avoided the kind of repeated position that would have given the champion a rule-book draw.

In Seville, grandmasters at the match were predicting that Kasparov could attain a draw, but many stressed Karpov's mastery in simple endgames.

Victor Korchnoi, who unsuccessfully challenged former champion Karpov for the world title in 1978 and 1981, said the challenger had no chance of winning but added: "He will play for a long time tomorrow."

Korchnoi praised Kasparov's play after the elimination of queens from the board, saying Kasparov found the best way of creating the possibility of a draw.

Seen against the background of Game 18, Game 19 looked like a pair of slaps in the face exchanged between the two players. In their opening moves, the two games formed a sort of mirror-image pair: the same opening, the same variation and the same moves, except that the players had swapped colors. This was essentially Kasparov's choice, and a strange psychological tactic. In effect, the champion seemed to be offering to teach the challenger the opening he had chosen in the previous game; or at least, he was saying, "I can play this opening as well as you can."

But could he? He later found out that things were not so easy. Karpov moved into a different line with his 14. Qb3, and secured a slight advantage. Black's pieces were entangled on the b-file, and the black isolated pawn on d5 was weaker than its white counterpart on d4.

For strategic purposes, it is a disadvantage to have pawns on squares of the same color as your bishop. Kasparov realized that he might be getting squeezed. Like most young players, he dislikes cramped positions and always seeks active play for his pieces. So he sacrificed a pawn to reduce white's pressure.

With his 20. ... Qd6, Kasparov threatened 21. ... Ba6, which would win the exchange, rook for bishop. So Karpov was forced to exchange queens, lacking time to play 21. d5 and consolidate his position.

After the exchange of queens, on first glance, Kasparov seemed to have enough play to compensate for his small material deficiency. But after 25. Nxa7, he played ... Be4, realizing that 25. ... Rb8 would be met strongly with 26. Rfc1. Thus, he was forced to go into a rook endgame where white had a protected passed pawn and his only hope was that somehow he might be able to build an impregnable fortress.

In the adjourned position, the fact that there are four rooks on the board is in Kasparov's favor; his rook on the sixth rank can be used not only to keep the a-pawn under attack but to bar the white king from getting into the action on the queenside. Without that barrier, white could threaten to march his king over to the a-pawn, attack the black rook and push the pawn down to its queening square. If the black king also marched to the queenside, black could then change tactics and win on the undefended kingside.

But with four rooks on the board, if there is a win for white, the path to victory leads through the kingside for white. That's one reason why he had his king on f4 at adjournment. If he can use his king and pawns to create kingside weaknesses and break into white's position, he may then be able to mobilize his rooks for decisive threats on the kingside.

The winner will be the first player to win six games or score 12 1/2 points. Kasparov keeps his title if the 24-game match reaches a 12-12 tie.

Grandmaster Lubomir Kavalek contributed to this report.