Arne Slot feared he was watching a familiar tale of frustration before Darwin Núñez broke through twice in stoppage time to seal an invigorating 2-0 win for Liverpool at Brentford. Slot introduced the 25-year-old as a 65th-minute substitute and it was easy to see the scene as being set for the club’s record signing, given how he has struggled in goalscoring terms this season.

Núñez would make the difference, scoring with Liverpool’s 36th and 37th shots of a game they controlled. He was helped by another substitute, Harvey Elliott, who started the move for the breakthrough and made the assist for the second.

Related: Darwin Núñez’s injury-time double at Brentford keeps Liverpool on title track

Slot’s mind had gone back to three of Liverpool’s most recent games – the Carabao Cup semi-final, first-leg defeat at Tottenham and the Premier League draws against Manchester United and Nottingham Forest.

“Yes, I had doubts about [Liverpool scoring] because before we scored the two goals it felt that I was looking at the same game again and again … the same pattern arose,” he said. “Against United, everybody was focused on the [Harry] Maguire chance [in the very last action] but in the seven minutes before we had three open chances.

“So many times in recent weeks – against Tottenham as well – we missed a lot of chances. Against Forest we missed a lot so it would be a bit surprising if I felt after all these chances missed today we will probably score in the last five minutes.

“We were close to not getting what we deserved. But the players proved me wrong again. If we would not have scored then the headlines would have been: ‘Liverpool dropped points – again.’ And no one would have told you: ‘37 shots.’ What a display. How many teams were able to have 37 shots against Brentford?

“It is the industry we work in. We all accept and understand that there’s a lot of focus [on the result] if it doesn’t go well and not as much on the fact if you give a great performance. It’s about winning and losing and not whether you play beautiful football. People only enjoy beautiful football if you win. Otherwise there’s no focus at all on the performance.”

Slot urged people to look at the xG statistics against United, Forest and Brentford. “You will then probably see that nothing has changed with us between now and the first half of the season,” he said. “What you do see is that, at this moment in time, it is a bit harder for us to convert our chances into goals.”

The Liverpool captain, Virgil van Dijk, said: “If nobody is ready for a bumpy ride then this season will definitely be one. Today was a small piece of the puzzle. We have to keep going. Darwin has brought a lot of energy since the day he came in. As a striker you’re judged by your goals. He had a massive part of the victory.”