The Jambos host the Scottish champions at Tynecastle on Saturday on the back of a 2-0 defeat to league leaders Inverness but Locke is going into the contest with plenty of positivity even with the Hoops preparing for Wednesday's Champions League clash with AC Milan.
"We're playing against the champions who have a team full of international stars. It is a great test for our young players," he said.
"There is more pressure on their players but that's the thing about playing for a club the size of Celtic, there are demands on them to win every week.
"I don't know what Neil is thinking with regards to his plans for their Champions League game. He might make a couple of changes, he might play his full-strength side and that's certainly what I think will happen.
"He will admit that Tynecastle is a tough place to come to and I'm sure he will come here wanting to take three points."
Hearts currently sit at the foot of the SPL table because of their 15-point deduction for falling into administration, however, their record would have them sitting seventh if all things were equal.