Tompkins struck in the third quarter of the 44-19 victory at Allianz Park, having come on as a replacement for injured captain Brad Barritt, who is set to be ruled out of the Twickenham showpiece on Saturday by a torn hamstring.
The 24-year-old centre was part of the England Under-20 side captained by Maro Itoje that won the Junior World Championship in 2014, yet his career has developed less spectacularly compared to his Saracens team-mate, who was magnificent against Gloucester.
“You look at it and say, ‘why am I not doing as well as Maro?’ Well, I’m not a freak and he is unbelievable!” said Tompkins, who ran in the three tries on his 100th appearance for the club.
“You’ve got to realise everyone is different, everyone takes their own journey. And that is tough, I would say that takes time and that takes a bit of maturity as well.
“When you are younger, you are throwing your toys out of the pram, you want to be there straight away.
“That’s one of the great lessons I have learnt at this club – biding my time. But you have got to keep working, because if you stop you go backwards.”
Barritt’s hamstring problem has created an opening in the starting XV for the final against Exeter, but chances will continue to be limited for Tompkins next season, when Duncan Taylor returns from injury and Elliot Daly arrives from Wasps.
“It’s tough, it’s really tough, because you have got to weigh up whether you are doing the right thing and ask if you are good enough,” he said.
“You have all these sort of questions going through your head and you have to look closely at those. But you also have to work hard. You can’t give up.
“There’s an element of biding my time and pushing myself knowing that I can be in this team and contribute.
“Having that self-belief is one of the hardest things, but it is also easy when you have great people around you.”
Jim Hamilton on Bastareaud’s MLR impact:
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