We present Monte Carlo data for a linear chain with excluded volume subjected to a uniform stretching. Simulation of long chains (up to 6000 beads) at high stretching allows us to observe the signature of tensile blobs as a crossover in the scaling behavior of the chain scattering function for wave vectors perpendicular to stretching. These results and corresponding ones in the stretching direction allow us to verify for the first time Pincus prediction on scaling inside blobs. Outside blobs, the scattering function is well described by the Debye function for a stretched ideal chain.