Janes returns to the Havant starting line-up for the first time since breaking his nose earlier in the season.
Knight believes he is just the man for such a tough assignment.
The Havant head coach said: ‘Richie has been a key component in our side for the past four or five years.
‘He has cemented himself in as a regular first-choice.
‘Though not the biggest player in his position he always brings great physicality to his game.
‘There is an intensity to the way he plays and he certainly punches above his weight.
‘He is also an excellent operator at the lineout and almost plays like an extra back-row forward. He is working his way back to full fitness but it is a bonus having him available for the run in to the end of the season.’
Unavailability means Havant are forced to make a number of changes.
Tom Blackburn, normally a front row player, switches to partner Janes in the second row.
Dan Porter moves to the back-row with Will Owen starting at number eight.
A senior debut is given to Harrison Chalk, who has come through the academy at number seven.
In the three-quarters Ben Chambers is unavailable due to Royal Navy rugby duties.
Jerome Rudder takes his place at full-back.
Despite the changes Knight insists his side are capable of causing an upset.
He added: ‘We have shown already this season that we are capable of beating the teams at the top.
‘Camberley, Brighton and Thurrock have all been beaten. It will be tough, though, because Sevenoaks are probably the best team in our league.
‘They are just one point behind leaders Medway so they will be up for the game.
‘In a way that can work in our favour.
‘All the pressure will be on them because they will feel it is a game they have to win.
‘We can go up there with nothing to lose.
‘The only pressure on us is the pressure we put on ourselves to produce a good performance.
‘At our place we lost by a single point in the final play of the game eight minutes into stoppage time.
‘It is always good to go out and test yourself against the best and it should make for an interesting afternoon.’
With Havant realistically moving towards a safe mid-table finish Knight feels it is important not to let the season fizzle out.
He wants the club to achieve the highest finish possible.
At the same time he has one eye on the future.
Knight added: ‘We are keen not to let things lapse.
‘It will also give us a chance to give a few guys coming through an opportunity.’