The unofficial start of summer started this past weekend, but we're dreaming about the fall. With that in mind, we're looking at the most indispensable players on each Big Ten team.

By indispensable, we don't necessarily mean best. We mean the players who would be hardest to replace between now and the start of the season if they got hurt/suspended/involved in a time-travel mishap, etc. That could be because of their value to the team or because of a lack of depth at their position.

We'll pick two players from each team, usually offense and defense, but not always. Next up: the Illinois Fighting Illini.

Josh Ferguson, RB, Sr.

Others undoubtedly must step up if Illinois intends to maintain last year's offensive production, but Ferguson remains the linchpin. He's one of the Big Ten's more explosive and versatile offensive weapons, displaying top-end speed and the ability to contribute both as a runner and a receiver. Both his yards-per-carry average and yards-per-reception averages have increased in each of the past two seasons. Ferguson led Illinois in rushing last year, averaging 5.5 yards per attempt, and finished second on the team in receptions with 50, setting the single-season team record for receiving yards by a running back (535). Illinois' depth at running back isn't as dire as it was when coach Tim Beckman arrived, but Ferguson does so much to help an offense with plenty of question marks outside of the line. The Illini need to keep No. 6 on the field.

Mason Monheim, LB, Jr.

There simply aren't many guarantees in Illinois' defensive front seven, especially with Houston Bates leaving the team in late February. Although linebacker T.J. Neal had a good spring and Mike Svetina brings experience, Monheim remains the nerve center of the defense heading into his junior season. He has 183 tackles in his first two years, including 12.5 for loss, to go along with three forced fumbles. He had seven or more stops in eight of 12 games last fall. Without Brown, Monheim is the undisputed leader of a unit that has to make significant strides, especially against the run, for Illinois to have a chance at making a bowl this fall. Few recent Big Ten linebackers have been as productive early in their careers as Monheim, whose best days should be ahead of him.