Mere semantics...the point is, John baptised with water, why is there no evidence Jesus did this, and if it was a new ritual started by John, how was that function fulfilled between Johns death and day of Pentecost?
Understanding this means understanding some things about Jewish practice. Specifically in Judaism ritual washing (called tevillah) was done for a number of reasons. These washings were to be done, usually, in a specific bath called a mikveh--wealthier Jewish households had their own mikvehs, but most Jews had to rely on public mikvehs.
St. John the Baptist, under his specific appointment as the Forerunner of our Lord, was in his prophetic work calling Israel back to repentance in the anticipation of God's imminent salvation and visitation to Israel, long ago promised by the ancient prophets, looking forward to the Day of the Lord, and the advent of the King Messiah son of David.
John's baptism/tevillah was a call for people to come and purify themselves in repentance through this ritual washing which John was doing. So what John was doing wasn't instituting a new ritual, but taking an existing ritual and imbuing it with a specific significance--the significance of repentance in anticipation of the advent of God's salvation into the world through the arrival of the promised messianic deliverer.
When Christ instituted Baptism for His Church, that was both a "new ritual" but also placed in the already established context of what was already familiar--the washing of water as an activity of God's mercy and power in a person's life is already established in the precedent of what had come before. But Christ takes what came before, and imbues them with His authority and power, giving them the significance of Himself.
Which is why when St. Paul encounters a group of "disciples" near Ephesus he discovers that they are horribly uninformed, which causes him to ask, "What baptism have you received?" And they respond that they had received John's baptism--and it is from here that Paul had to illuminate their minds by giving them the full picture, and then provides them with Christian Baptism.
John's baptism was a baptism of repentance in anticipation of Christ; the Sacrament of Holy Baptism which the Church administers in Christ's name, authority, and stead is that which Christ Himself instituted and gave for the purposes with which He gave it. So, for example, we read in the 2nd chapter of the Acts of the Apostles that this specifically Christian Baptism, "in the name of the Lord Jesus", washed away sins and conferred the promise of the Holy Spirit (Acts of the Apostles 2:38), and that this Baptism was for both those hearing these words (many very likely were familiar with John's baptism, and many may have even been washed in John's baptism), and for their children, and for all who are far away--all whom God shall call to Himself.
And so the word of the Gospel came out of Jerusalem by the preaching of the Apostles, empowered by the Holy Spirit on the Day of Pentecost to the whole apostolic work to which they were called. They preached the word, and those who heard the word were received into the Church through Baptism, even entire
oikia, households, were baptized as we read in a couple places in the Acts of the Apostles.
Thus Christian Baptism has antecedent and precedent in what came before, even as the precious Eucharist which we celebrate is grounded in Paschal Seder, with Christ imbuing the breaking of bread and the drinking of the cup with new purpose and meaning. That the meal of remembrance of God's deliverance of Israel from Egypt is now fulfilled and given new and special meaning in a new sacred supper instituted by Christ--wherein here in/with/under these elements of bread and wine is Christ Himself fully--His flesh and His blood, broken and shed for us and for our sins. For which reason this Supper was of such sacred importance that St. Paul gives a strong warning against abusing the bread and wine of the Supper, because to sin against the Eucharist is to sin against Jesus' own very bodily flesh (because that is what we have here in the Supper, Christ's flesh and blood, 1 Corinthians 10:16).
These sacred pledges from God to us, in which God works the revealed mystery of His redeeming and saving grace in our lives are called variously mysteria in Greek ("mysteries" because these are revealed acts of God's grace for us) and in Latin came to be called sacramenta, sacraments, meaning "a sacred pledge"--God's sacred pledge to us through these precious means which Christ has given, and the seal of God's grace and Spirit on us and our lives. In Baptism we have been "stamped" as it were with the very name of the Father, Son, and the Holy Spirit, the Holy Trinity; that is the kind of gift, work, and power of God this is for us.
-CryptoLutheran