Roberto Martínez believes Everton are showing Champions League potential this season but must deliver on a consistent basis to be considered genuine candidates for a top-four finish.

Everton visit West Bromwich Albion on Monday looking to improve on a steady start to the campaign that has brought victories over Southampton and Chelsea and three successive away clean sheets in the league. Martínez insists it is too early to assess Champions League qualification credentials, claiming that can only be done after 10 games, but cites the Chelsea and Southampton displays as the standard required to challenge the established order in the Premier League.

“We don’t need to rely on other teams,” said the Everton manager. “We rely on how good we can be and how quickly we can get to that level. The Southampton performance and the Chelsea performance – that’s the level that is needed to get into the Champions League, top and bottom. If you can do that every week you’re going to have a great chance to get over 70 points.

“How many points are going to be needed this season? It’s hard to tell but I think it’ll be such a close season. You look at the points West Ham have got away from home and Crystal Palace’s form. There are many teams who are going to take a lot of points from the so-called top four. That makes me think 70 points will get you into the top positions. It is about consistency.

“It is down to us being as consistent as we can be in every game. It is not about looking elsewhere or what is happening with the investment in other teams. I’m excited. I’m starting to see signs of a very competitive squad and hopefully we can develop that for the next eight months.”

John Stones and Seamus Coleman are doubtful for the game against Tony Pulis’s side with knee and hamstring injuries respectively. The £9.5m summer signing Ramiro Funes Mori will make his first Premier League start for Everton should Stones fail to recover from a medial knee-ligament strain in time.

Romelu Lukaku returns to the club where he scored 17 goals while on loan from Chelsea in 2012-13, having missed decent chances in Everton’s goalless draw at Swansea City days ago. But Martínez said: “Rom is one of the most clinical strikers around. If Rom creates the amount of chances he did against Swansea then we will never have a problem. Converting those chances against Swansea comes down to a little bit of luck or a bit of good form. His finishing is his biggest strength. His contact is clinical so I wouldn’t be worried about that.

“We know what to expect – a very experienced side who take pride in themselves in playing at home in front of their fans, and a team that is able to score a goal.”