Doncaster Rovers Belles head coach Glen Harris wants more of his side, despite opening their Women's Super League Two season with a 3-0 home win over Durham.
The Belles are early league leaders after goals from Courtney Sweetman-Kirk, Bethany England and Sue Smith.
"The players know, I know, the staff all know we will need to improve on that," Harris said.
Elsewhere, Fran Kirby scored all four of Reading's goals as they beat Yeovil 4-2, while Oxford overcame Watford 1-0.
Captain Sahara Osborne-Ricketts, who scored the only goal with a low free-kick on 20 minutes, almost added a second in stoppage time at the end of the game, crashing another set-piece off the crossbar.
Kirby, the top scorer in England's top two tiers last season, opened her account for 2015 inside six minutes against the Glovers.
Tash Knapman levelled with her first goal for Yeovil, only for England international Kirby to complete a first-half hat-trick with two goals in as many minutes just before the break.
Corinne Yorston pulled a goal back on her Yeovil debut, converting from the penalty spot after Annie Heatherson was brought down by Reading goalkeeper Grace Moloney.
While it gave the hosts hope of salvaging a point, Kirby eventually sealed victory for Reading with a well taken fourth in injury time.
"Fran wouldn't score those goals if she didn't have the service," said Reading manager Kelly Chambers. "She's a goalscorer and this is why we've invested in her and we want to keep her."
Doncaster, who are among the favourites alongside Reading and Everton to win promotion to WSL 1, failed to seriously trouble Durham at the Keepmoat Stadium until Sophie Barker hit the bar with an effort from outside the box in first-half injury time.
Durham were brightest before the break, with Portuguese midfielder Amelia Pereira particularly lively on her league debut.
Sweetman-Kirk opened the scoring and England made it 2-0, lifting the ball over Helen Anderson, before Smith's curling effort completed victory.
Kasia Lipka went close to adding a fourth, but her effort skimmed the bar.
Harris continued: "You're going to be a little bit nervous on your first game, but I had faith in the girls, I trust the girls, and they showed great patience and great quality.
"We told the players at the beginning that they need to be patient and they did that, so I'm happy with that."
Durham manager Lee Sanders said Doncaster had proved themselves worthy promotion candidates.
"We've had arguably the hardest start that we could have had," he said. "We went in level at half-time and obviously Doncaster are a great side - one of the favourites to win the league - but one half isn't good enough."