The Spanish coach was proud of his team’s performance and noted the financial differences between the two clubs
Goals from Lukaku and Christian Eriksen saw Inter record a 2-0 win over the La Liga side in the last-16 clash in Gelsenkirchen on Wednesday.
Signed by Inter from Manchester United for a reported €80 million (£72m/$95m) last year, Lukaku has scored 30 goals this season.
Getafe boss Bordalas said the difference between his team and Inter was enormous, highlighting how much Lukaku cost.
“We are sad because I think the team played a great game,” he said.
“We had Inter on the ropes during the second half. We had control of the game and, unfortunately, in our mistake in their first goal after practically nothing had been put forward, but the team did not fall and we had the penalty that would have put us fully into the possibility of passing this tie.
“It is a shame, but I am proud because the approach has been fantastic, the team has interpreted it great. I am very proud of the work of the players.
“The difference is very big, only Lukaku cost the same as all of Getafe.”
Speaking after the win over Getafe, Lukaku stressed his focus was already on the next match as he urged Inter to improve.
“We knew it would be a difficult game, against an aggressive team,” Lukaku told Sky Sport.
“The defence did a really good job and we did well at the front. I’m happy with my goal, and Christian’s too.
“I want to win and continue to help the team. The work we’re doing with the coach is really important. The team is growing and we need to move ahead with the same mentality and desire to improve.”
Lukaku, who equalled a Europa League record after scoring in his eighth straight match in the competition, could face off against his former club Manchester United if both make it to the final.