Portsmouth defender Regan Poole says his side are going to face "an uphill battle" this season if they continue to concede set-piece goals.Tuesday's 3-0 defeat at Bramall Lane saw Pompey concede twice from Sheffield United's first five corners, leaving them 20th in the table, two points outside the relegation zone."It's a problem, of course," Poole told BBC Radio Solent. "It's something that needs to change, otherwise we're going to be fighting an uphill battle every game because teams are going