Sliding clamp that encircles the genomic DNA and links the DNA polymerase to the template to control the processivity of DNA synthesis. Responsible for tethering the catalytic subunit of DNA polymerase to DNA during high-speed replication. Interaction with the sliding-clamp-loader opens the sliding clamp so that it can be loaded around the DNA template. During transcription, encircles the DNA and tethers host RNA polymerase (RNAP) to it. Homotrimer. Interacts with the viral DNA polymerase; this interaction constitutes the polymerase holoenzyme. Interacts with the sliding-clamp-loader; this interaction allows the sliding-clamp-loader to open the sliding clamp. Interacts with the viral DNA ligase. Part of the replicase complex that includes the DNA polymerase, the polymerase clamp, the clamp loader complex, the single-stranded DNA binding protein, the primase, the helicase and the helicase assembly factor. Interacts with the viral RNA polymerase (RNAP). Part of the transcription activation complex containing host RNAP, the viral RNA polymerase sigma-like factor, the late transcription coactivator, and the sliding clamp. Belongs to the Tevenvirinae sliding clamp family.