The Grecians went ahead through a Joel Randall strike before Gyebi was red carded for a reckless challenge.
Tomlinson received his first booking for fouling Randall in the area, but the young winger couldn’t add to his earlier strike from the spot with Tommy Scott making a smart save.
The second half provided little of note with regards to chances but Yeovil coaches Paul Wilson and Antonio Falanga were sent from the field and Tomlinson was shown a second yellow for shirt pull.
Exeter made a bright start to the encounter and Scott produced a good stop with his feet before Randall nodded a free kick wide.
Nestor Sako hit a wild shot over the crossbar and was then denied by a last-ditch tackle as he raced through on goal.
The away side took the lead on 20 minutes when Randall collected a crossfield pass, skipped down the left and finished with aplomb at the near post.
It sparked the hosts into life and when Jack Rice-Lethaby’s cheeky back heel found Sako, the striker aimed towards the far corner and goalkeeper Felix Norman did well to palm round the post.
The Glovers were reduced to 10 just past the half hour mark. Gyebi lunged for a loose ball in the midfield but in turn connected with an Exeter player.
Samyan Ismail was booked for his protests and the referee had his yellow card out again moments later as Tomlinson fouled Randall in the box.
The Exeter man stepped up to take the resulting penalty but Scott got down to his left to tip away superbly.
In the second period, Yeovil defended admirably despite City being a man to the good.
The referee turned the game into a stop-start affair towards the end, first sending off Falanga before Tomlinson was given a second booking. Wilson then got the same treatment as his counterpart.