work out the lowest market_index of markets in play

Hi folks, me again, I'm still puzzling on how to pick one market out of several that are in play when each one may have a matching selection.

Is it possible to use the market_index ? I would like to do the following -

Say there are four matches in play, all kicked off at different times but similar so the games are pretty evenly matched for over 0.5 goals.

My trigger goes off when it has a matching selection, but if there several games which have a matching over0.5 goals selection, it goes off for each one. I'd like it to work out which is the market that's been in play the longest out of the four being monitored and just bet in that one?

Is it possible - somehow workout the lowest market_index of the four in play ?
Rich

I have tried different combinations but I just could find a way to do this.

Untested, just brain storming

Create a market (not global) variable now_time - event_off (This will give you time in play)
Lets call the variable inpley
eg. inpley then  use inpley_market_id =MIN(other inpley's)

Do you get what I mean?