Eriksson's free-scoring forwards mask Leicester's defensive issues

Sven-Goran Eriksson could not remember winning another match by a 5-1 margin since he supervised England's historic demolition of Germany in September 2001 yet he conceded that Leicester's ambitious owners might be best advised to think less about signing superstars to instead finding solid, savvy defenders if they are to secure a rapid passage to the Premier League.

The Swede has been pursuing David Beckham, Robbie Keane and Roque Santa Cruz as his Thai employers seek a marquee signing in the January transfer window but knows that Leicester's goals against tally could prove their undoing, regardless of the attacking flair at his disposal.

Leicester's emphatic second-half romp, which culminated in the 5-1 win over Doncaster Rovers, disguised an error-strewn first half in which they could have been three behind before a contentious penalty prompted a Doncaster collapse. Billy Sharp opened the scoring for the visitors in the seventh minute after James Coppinger had been allowed a free run into the Leicester box and had James Hayter and David Healy not been profligate with their finishing, two more Doncaster goals at least would have preceded the penalty award against goalkeeper Neil Sullivan's ball-winning slide into Lloyd Dyer.

"Doncaster had played some very good football, we were lucky to get the penalty in the last seconds of the first half," Eriksson said. "They were running through our midfield, behind our defenders and we were not countering it. I knew we could not go on like that."

Three of Saturday's back four – full-backs Kyle Naughton and Greg Cunningham and centre-half Curtis Davies – are on loan from Premier League clubs but Leicester's defensive record, with 35 goals conceded, is still better only than the teams in the bottom three.

"If you look at the back line, they are excellent players and they should be extremely good at this level but unfortunately we sometimes make mistakes," Eriksson said. "If we had not done that, especially away from home, we would have at least two points more, maybe six. A couple of times away from home I don't know how we have lost.

"Yes, the owners would like a big-name signing. But the priority is to sign players who are better than those we have, whether they are a big name or not. If we don't we aren't going to do anything."

As it is, Eriksson is not short of attacking potency. As Doncaster wilted, a front six, in which Andy King's intelligent linking and perceptive passing caught the eye, ran riot with Richie Wellens, Naughton, an increasingly sharp Darius Vassell and substitute Martyn Waghorn taking full advantage.

Leicester City (4-2-1-3): Weale; Naughton, Davies, Vitor, Cunningham; Abe, Wellens; King; Vassell (Oakley 86), Bednar (Dyer 37), Gallagher (Waghorn 78). Substitutes not used Logan (gk), Fryatt, Moussa, Hobbs.

Doncaster Rovers (4-1-2-3): Sullivan; Martis, Hird, Thomas, O'Connor (Guedes 75); Stock; Coppinger (Wilson 86), Oster; Healy (Shiels 76), Sharp, Hayter. Substitutes not used Woods (gk), Brooker, Lockwood, Fairhurst.

Referee J Linington (Hampshire).