Rangers hosted the Dutch runners-up in Glasgow on Tuesday in the league path of Champions League qualifying.
The Gers havent made the Champions League group stage in 12 years but will need to triumph in Eindhoven.
PSV took a 37th minute lead via Ibrahima Sangare’s thumping finish, but the Gers hit back with Antonio Colak equalizing before half-time.
The Scottish giants took the lead in the 70th minute from Thomas Lawrence’s free-kick that was spilled by PSV goalkeeper Walter Benitez.
But PSV found a route back to square it up with Obispo heading home the leveler ahead of the second leg in Eindhoven next Wednesday.
Rangers’ Dutch boss Giovanni van Bronckhorst said: “I’m a very positive person and of course we are able to go through.
“We have showed in the past we can get a result away from home.
“It’s still even. We have to go out there and play for everything.”
Elsewhere, Norwegian club Bodo/Glimt, who had a dream run in the UEFA Conference League last season, edged Dinamo Zagreb 1-0.
Danish champions FC Copenhagen beat Turkish outfit Trabzonspor 2-1 to put themselves on the brink of qualification.