Springboks loose forward Pierre Spies says that the Springboks let themselves down by drawing 14 all with England in Port Elizabeth on Saturday.

"England placed us under pressure and they wanted to come away with a result tonight [Saturday]," said Spies who was playing his 50th Test for the Springboks.

"We also wanted to win, but we just didn't fire, and they forced us into errors and put our lineouts under pressure."

The English dominated the tackle area, where they also slowed the Boks' ball.

Spies admitted that the team did not play well and they had to make improvements ahead of the Rugby Championship starting in August.

"It was certainly not our best performance as a group, and it is a pity because we really wanted to win all three games," he said.

"There are a lot of things we can work on with an eye on the Rugby Championship."

Despite bagging the series, Spies said the Springboks were disappointed in falling short of a whitewash over the Roses.

"We set high standards for ourselves and as a group we want to win all our games in SA," Spies said.

"So, in that sense, we let ourselves down tonight because we wanted a victory, even if it was by only one point, but we ran out of time."

Reflecting on earning his 50th cap, Spies said he had to adapt his game as the opposition had figured him out over the years.

"The older you get, one changes and one is thankful that you are part of the set-up," he said.

"But it also makes you realise that you have to change your game.

"If I look at myself now, I am not the same player I was when I was younger or as brutal, but I am tougher and wiser in a sense."