Robbie Neilson warned Hearts that they have just 10 per cent of the job done, with all eyes now on the Scottish Cup semi-final against Hibs next weekend.
The Jambos boss also applauded Andy Halliday's "outstanding" double goal-scoring display in the Edinburgh Derby, explaining that the stand-in midfielder "thrives" in high-pressure environments.
The 30-year-old netted the equaliser just before half-time against Hibs and his second - the Jam Tarts' third - in the second half of their 3-1 win.
Neilson cautioned his side still have work to do after their league derby win, with the remaining 90 per cent coming next week.
"It was a good performance," he told BBC Sportsound.
"It's great to get the three points and secure that third place, having just been promoted, but all eyes are on next week and the Scottish Cup semi-final.
"Next Saturday's game is the big one for us because not only does it get into a Scottish Cup final, not only is it beating your nearest rivals, it's also an opportunity to make sure you get group stage football which is the most important thing.
"Yes today was brilliant because it was all about winning the derby in the league, but in my opinion we've done 10 per cent of the work today - 90 per cent is next week."
On Halliday, he added: "I thought he was outstanding.
"Andy thrives in these environments, he thrives on the oppositions fans going after him, the pressure of playing in the big games.
"In my opinion, he's a real top player and he showed it today. He had a couple of opportunities and didn't take them, but he keeps going and he gets the first goal and then the next one.
"I'm delighted with him."
