Before each session in the Ryder Cup, is either captain aware of the opposing team's lineup for that session?

Question

Are the lineups of both sides submitted without knowledge of the opposing lineup? If not, which team submits its lineup first? Can the lineups be modified once submitted?

Answer 1

The teams of twelve are largely determined by a ranked list system, and completed by a captain's pick.

Players eligible for the USA team earn points from certain competitions on the pro circuits, and the top eight players as of the end of the last tournament that awards points are automatically selected.

Players eligible for the European team earn points at corresponding competitions in a similar way. The top four players on the European list are automatically selected, followed by the top four players on the World list.

In both cases, the remaining four spots are picked by the captain of the team, in whatever manner they may have determined or otherwise been instructed to use.

Answer 2

Are the lineups of both sides submitted without knowledge of the opposing lineup?

Though I cannot confirm, I'd imagine so. Otherwise, there is a possibility of tampering with the lineups to gain competitive advantages. The following quote (also found below) alludes to strategy being used when a team sets their lineup, and the captains only have knowledge of the other's lineup after the lineups are submitted when they are announced (if not shortly before announcement).

Do you send out your strongest players first? Or hold them off in anticipation of The Ryder Cup coming down to one of the final matches? Captain Bjørn and Captain Furyk will assess the scoreboard, and their team, before setting the order in which their 12 players will be sent out. After cementing their respective line-ups, the captains will reveal who will face-off in the final session of The 2018 Ryder Cup.

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If not, which team submits its lineup first?

According to the Ryder Cup themselves, the captains have a window of time to submit their lineups. It is not clear whether one team is required to submit their lineup before the other team, but a team is required to submit their lineup before a specified time.

Below are the deadlines for submitting pairings during the 2018 Ryder Cup:

Friday, September 28

12:35- 13:05: Afternoon pairings submitted - As the opening session draws to a close, both Captain Bjørn and Captain Furyk will have a short window of time to make any necessary adjustments before they set their line-up for the afternoon foursomes matches, which is an alternate-shot format.

One hour after play: Saturday morning pairings submitted: Following the conclusion of Day One, both captains will have time to consult with their Vice-Captains and their players before they are required to submit the pairings for Saturday morning’s fourball matches no more than one hour after the second session is completed.

Saturday, September 29

12:35- 13:05: Afternoon pairings submitted - With the point totals beginning to add up, each captain will have a better sense of how his players are faring, and the submission of Saturday afternoon’s foursome pairings offer Captain Bjørn one final chance to send out the strongest two-man teams, as well as rest key players before all 12 compete in the Sunday singles matches.

One hour after play: Decision time. Do you send out your strongest players first? Or hold them off in anticipation of The Ryder Cup coming down to one of the final matches? Captain Bjørn and Captain Furyk will assess the scoreboard, and their team, before setting the order in which their 12 players will be sent out. After cementing their respective line-ups, the captains will reveal who will face-off in the final session of The 2018 Ryder Cup.

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Can the lineups be modified once submitted?

I'd imagine not. The following quote (also found above) alludes that lineups are final.

After cementing their respective line-ups, the captains will reveal who will face-off in the final session of The 2018 Ryder Cup.