How to linearly detrend data before 3dDeconvolve

Hello afni experts,

I am doing my data processing mostly in afni (resting state), but I would like to use antsR to calculate CompCor principal component regressors for wm and csf and use them again later in afni as nuisance regressors. The input data required for the calculation of Compcor regressors should be slice time corrected, motion corrected and linear trends should be removed. So my question is what function exactly can I use to remove only linear trends from the motion corrected data?

I read in this message board that it would be 3dTproject but after I looked at the -help output for this function I still don t understand how to use it for linear detrending.

Thank you very much in advance