The disclosure relates to a system for liquid sample introduction into a chromatography system. The system includes a syringe, a first valve in fluid communication with the syringe, a second valve in fluid communication with the sample, a vessel located between, and in fluid communication with, the first and second valves, a third valve in fluid communication with the first valve, the second valve and a chromatography column, and a pump in fluid communication with the third valve and a mobile phase. When the valves are in a first position the syringe draws the sample into the vessel. The mobile phase flows to the chromatography column. When the valves are in a second position, a portion of the mobile phase flows into the vessel, mixing with and pressurizing the sample. When the valves are in a third position, the mixed and pressurized sample flows to the chromatography column.