Bulls skipper Robbie Paul believes St Helens might not be able to forget they are playing in a cup final seven days later when they take on Bradford at Valley Parade on Saturday.
"It is a hard thing to do," said Paul, who has been in the same situation four times with the Bulls.
Saints face Wigan at Murrayfield on April 27, and Paul said: "The Challenge Cup final is such a big game - probably the second biggest of the season.
"And I hope it affects St Helens to be honest.
"They have been together for quite a few years and had a lot of success so they may have the experience to cope, but the final is always there in the back of your mind. However, Saturday is a big game in its own right.
"It is first v second in the table and, throughout the history of the Tetley's Super League, Bradford v St Helens have probably been head-to-head in more big games than any other two teams."
Summing up Saints, though, Paul said: "They are erratic.
"You may be five points ahead of them with the last play of the match to come and they will score a try and a goal.
"And I cannot tell you how frustrating a feeling that is when you are on the wrong end of it as we have been."
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules hereComments are closed on this article