Quickstart notes
Fetch tomorrow's matches with the prematch board
One parameter switches the markets call from live to prematch: event_type=prematch. The same envelope returns fixtures, kickoff times and prices.
The live board shows what is happening now; the prematch board shows what happens next. Getting it takes one parameter on the same markets call: event_type=prematch, next to the sport ID. The response is the same envelope you already parse, filled with matches that have not started, each with its kickoff time and the current prices.
The parameter that switches the board
The Google Sheets quickstart asks for event_type=prematch alongside sport_id=1 and receives the prematch soccer board, as the Sheets page shows, checked 2026-10-05. The same parameter works from curl, Python or Node: it is the same markets route, the same events array and last cursor, and the same period structure underneath.
Live and prematch are separate calls with the same shape, so nothing you built for one breaks on the other.
What a prematch row gives you
Each event on the prematch board names the league and the teams and carries the scheduled start time, which is the field that turns a board into a watchlist. Filter on it: starts within the next 24 hours, starts this weekend, starts after your daily run. The full-match money line sits in period zero, exactly where the live board keeps it.
A useful habit is to fetch the prematch board once a day, keep the events you follow, and let your other polls ask only about those, instead of rediscovering the schedule on every run.
Following a match across the boards
A fixture lives on the prematch board until play starts, then leaves it and appears on the live board. When you track a match across that move, match it by the teams and the start time rather than assuming an identifier stays put across the transition; the pair of boards is the documented structure, and the handoff point is the kickoff.
This is also how you capture a closing line with polling: the last prematch snapshot before the start is the close, and the prematch board supplies the start time you measure it against.
Budget the slower board
Prematch prices move on a slower rhythm than live ones, so the prematch poll can run slower without losing anything. The pricing page lists the free key at 100 calls a day, checked 2026-10-05, and a prematch board polled every 15 minutes runs inside it all day, the same arithmetic the Sheets quickstart runs its timer on.
One parameter, one slower rhythm, and tomorrow's card is in your hands a day early.