The zip function, in action.

RandomizeScore.java

public Mono<ServerResponse> randomizeScore(ServerRequest request) {
    String countString = request.pathVariable("count");
    int count = Integer.parseInt(countString);

    if (count < 0 || count > 40) {
        return ServerResponse.badRequest().body(BodyInserters.fromObject("Count must be between 0 and 40"));
    }

    Flux<String> playerNames = this.teamRepository.findAll()
            .map(Team::getPlayers)
            .map(players -> players.stream().map(Player::getName))
            // collect lists into a Flux of Strings
            .flatMap(Flux::fromStream)
            // convert to a Mono of List<String>
            .collectList()
            .map(list -> {
                // work with the single unified list
                while (list.size() < count) {
                    // Double the size of the list until it's bigger than the count
                    list.addAll(list);
                }
                // randomize by shuffling order
                Collections.shuffle(list);
                return list;
            })
            .flatMapMany(Flux::fromIterable);

    Flux<Double> doubleFlux = Flux.interval(Duration.ofMillis(1000))
            .map(pulse -> this.randomDouble())
            .take(count);

    // combine the two fluxes and update player scores with random Doubles
    Flux<Team> updateFlux = Flux.zip(doubleFlux, playerNames)
            .flatMap(objects -> {
                Double scoreChange = objects.getT1();
                String name = objects.getT2();
                return this.updateTeam(name, scoreChange);
            });

    return ServerResponse.ok().body(BodyInserters.fromPublisher(updateFlux, Team.class));
}